White Opening System

Stonewall Formation

The advance of one insignificant pawn would not seem to have much impact on the overall strategies of White and Black. But it does. From White's point of view he knows that he no longer has to advance his e-pawn in order to attack. There are plenty of mating possibilities available without chanping the center further. Al1 he need do to abet this attack is to play-Nr3 followed by bringing a heavy piece to h3, e.g._Rfl- f3-h3 or Qdl-M-h3., Then- he has his forces lined up against

~ c T 1 i ; - i S ~ a h i ' c ~ l a r l y vulnerable after Black has castled. He can remove the-only defendq of h7 (when Black has played ... o-Q b f w 6 of NeS-g4 or g2-g4-gS.

C---- - i- -

And since he will not be pushing his e-pawn without a good reason, White can maintain the security of his d4 - unlike what Colle did in his game with Capablanca. A good exarnple of this was:

Intrduction: Wliite Operiirig Systerri 13

PILLSBURY vs MAJOR HANHAM New York 1893

White's attack proceeds naturally. Black had one ex- ellent -opportunity to block the "rnating'di~@ii3" wTh-

k . ; . ~ e 4 . .Now that -he.missed th5i bhance. Black is in bajor ' C_

trouble since the elirnination of themost ad;&ced White piece - - 10 ... Nxe5 - only gives White more room to attack after 11 fxeS!.

z Cc) Pa

C

O

.s H

.d

C, 2

c a&

O 1 oaj

WC

." 5

, s E E

o ;d

.- E

Sa

-2 Q

)

s g o

0 zg 3cdU

d

92

Cc-" u

.22

L

cd

o=

2 C

ZJ

2p

g t-',

3

cd

k

5; u

K-

Q)' Q

,

al2

2s

-- Q.2

3s M',,

&S

C 3

g yxo

2z

un

am

E.2

X-L

White Opening System

CHAPTER TWO

The Stonewall (Introduction)

We turn our attention now to more traditional methods of countering White's first two moves.

In the early days of 1 d4, back in the 19th Century. Black often played super-cautiously in the opening. You can still find many amateurs today playing this symmetrical way:

h The-choice.. of. a Stonewall or a Colle is up p ,y-04. )&

' we l ikr ihe Stonew-al!-if Black b l g c ~ s - h i s ~ u E n Bishop-?$h /Q; . ----. -. W - - . - . -- -----. ,, ... e .

Imitation is the sincerest form of flattery. But in chess it's the easiest way of getting a lost game. By duplicating his opponent's moves, Black usually places himself in the position of playing catch-up. If White can create a forcing position -- a position in which Black cannot imitate White's last move be- cause he must respond to a specific threat - then the symrnetry is broken, often with tragic results.

Notice, by the way, that Black can temporize with a "waiting move" such as 2...c6. This strengthens Black's center, just as 2...e6 does, but it";roFnot -____ I _ block in his QueekBishoa. as ,2..,ea_do?.But th_erejs.another problembwith.2?..c6. Black of- ten needs counterplay in the center to combat the Siònewall.

Chapter Two: 'I'lie Storie~rill 3 5

! This means that after 2...c6 3 Bd3 White is in an

position _to convert to t h e S t o e W 5 l E t h 4 f4!. Tt'S tiie bèst of i Stonewall worlds: (QBlack ha3 cbmmitted hisTiZGwTt6 the-

l --- -

fiiirth rarik, anT{b)-it Will iake hirn two nioves toxe't his c- -

pawn to the fourth-rank.

Black-can- also. play 2...Nf6 or-2 ... c5 a& transpose. into oui. nextchapter. Note. howevér, that moves such as 2...Nd7 o< -.

-. 2...&6?. encourage White to stop 3...e5 w i t h ~ g ! , thè= ohtairiiì~g a particularly favorable version of the Stonewall. --.-. .- ..

One unique situation that can arise comes about after 2...Nf6 3 Bd3, Nc6 and now 4 f4 (to stop 4..e5), Nb4!. This is ariclther move order that was once thought to be the definitive unswer to White's 2 e3. After 4...Nb4 White cannot afford to setveat the Bishop from d3, because then S...Bf5! will be too strong.

36 White Opening System Chapter Two: Tlie Storie\rall

The proper response then is 4. ..Nb4 5 Nf3, Nxd3ch 6 cxd3!. White surrenders Bishop for a Knight but gains some- thing valuable in retum: pawn contro1 over the key c4 and e4 squares. The result is a semi-closed position in which Knights may be worth more than Bishops. For an example of what may happen, see Illustrative Game 3.

This important move by White adds additional pawn protection for the center but, equally important, it provides a good retreat square at c2 for his Bishop. Remember the Colle- Delvaux game from the Introduction? Then the move ... c5-c4 turned out to be a major strategic error by Black.

For examples of an early ... Nf6, look to chapter Three. The advantage of 4...N- is that it threatens to play 5...e5!. a move that would b G positional refuìalion G f White'S strategy, e.g. 4...Nc6 5 Nd2, e5!, after which 6 dxe5, NxeS or 6 Ne2, Nf6 leaves Bhckwith an obviously better - - position in the cen- ter.

White can, if he p-fers, play 5 NM (Colle) as in Chap- - C - ,. --.-

ter F o u i "

This move creates a double-Stonewall with these fea- tures. Black: (a) shortens thF%taiEing diagonal of d3-h7. (b) assiires himself of his own outpost square at e4, while conced- ing e5 to White, and (C) makes it likely that if any file is going to be opened in the middlegame, it will be the g-file by way of g2-g4 or ...g 7-g5.

This last point is worth considering in a different light. Black can play the immediate S...g5!?. In a celebrated game froni before the turn of the' century- (Showalter-Maroczy, London 1899) Black obtained the better chances following 6 fxg5?, Qxg5 7 NM, Qg4! (better than 7...Q.xg2 8 R g l ) 8 Qe2, f5! 9 Nbd2, Nf6 10 Nfl, Rg8 with an initiative.

A simpler way of handling this for White is&-NO!,._, thereby preserving his pawn at f4. After 6...gxf4 7 exf4, cxd4 8 cxd4, Bg7 9 Nbd2 and 10 Nb3, Black has succeeded in isolat- ing White's d-pawn as a target. but White has the excellent outpost squares on e5 and c5. Note that 9,..Nxd4? 10 Nxd4, Bxd4 11 Qa4ch costs a piece and 9...Bxd4 10 Nxd4, Nxd4 11 0-0 is a risky gambit to accept.

And, once more, on 5,..Nf6 Black will transpose itito posi tions considered in thè next chapter.

White Opening System

Now Black can continue in various ways. including 7...Bd6, 7...Be7 or 7...Ne4. He will castle Kingside and (hopefully) be ready to challenge White on that wing.

A game Showalter-Marco, Cambridge Springs 1904 went:

Here White decided to gain unopposed contro1 of his outpost square by way of 9 BbS?!, Qb6 10 Bxcoch, bxc6 11 Ne5. But since he has parted with his good Bishop, Black can afford to give up his own (with ... Be7-d6xe.5) in order to obtain an equa1 game. A L--.- better ------ strategy - for ----. - White is open the King- side. Therefore:

- -

White's Middlegame Strategy

E r e c t j o u r attention towards the enemy. King. Since Black hasbòught a share oFthe f(ing5de with his fifth move, yoii will not be able to demonstrate a superiority with mere maneuvers, such as Rfl-M-h3. Therefore. you need to change the pawn strutture and open a file for your heavy pieces.

This means opening*? g-file. One procedure to ex- ecute this plan woula be 9 Khl followed by 10 Qe l , 11 Rgl and 12-g4&At some poinTyou may have to recapiure cìn e5 afl- tZr Black takes your Knight. In general, you should retake with the f-pawn. The exception is usually when dxc5 would allow you to occupy the now-vacant d4 with your remaining Knight.

t

White Opening System ('hapter Two: I'lie Stonelvali 4 1

Illustrative Game

(3) YATES-SCHLECHTER Pistyan 1912

As mentioned above, Black's fourth and fifth moves were once thought to be the way to defang the Stonewall, by eliminating White's best attacking piece. However, thanks to his sixth move, White can now play the position in a strategic manner, rather than in an all-out dash for the King.

Note his last move. The old rule about not playing Nc3 before c2-c4 in a l d4 opening makes sense when the Knight move blocks the C-pawn's advance. Here White no longer has a C-pawn, so his last move is perfectly normal. The..Knight, in fa&,& heading for e2 and possible use on the K&side (atg3) or in the center a t d 4 ' ( a f t e ~ ~ ~ 5 f d x c 5 ) . -

-

White nezd not obtain a mating attack to win: A good illustration of how this opening can lead to a won endgame is ~arshall-Suchting7ienna 1908:-Black %ed à t move six with 6...e6 and there followed 7 Nc3, b6 8 0-0, c5 9 Ne5, h5 (to avoid 9...0-0 10 g4) 10 Bd2, Bd7 11 Qf3, Rc8 12 Bel!, Be7 13 Ne2, cxd414 Nxd4, Bc5 15 Be3, b5 16 a3, a6 17 Qg3, KW 18 Racl, Rh6 19 Nb3, Bd6 20 Qg5, Be7 21 Ba5!, Qe8 22 Qg3, Ne8 and now 23 Nxd7ch, Qxd7 24 Rxcgch, Qxc8 25 Hcl, Qa8 26 Nd4, h4 27 Qf2, Nf6 28 QcZ!, Bd6 29 Qc6!, Qxc6 30 Rxc6, he8 31 Rxa6, e5 32 Nf5, Re6 33 Nxd6, Rxd6 34 Rxd6, Nxd6 35 Bb4 Resigns.

- v

10 Bd2 C5 11 Rcl Ba6 12 Ne5 Nd7 13 Qa4! .. .

Despite al1 the attention focused on the Kingside in Stonewall positioiis. White has an excellent game on the other wing here. The riext few moves are forced.

13 ... Nxe5 14 Qxa6 Nd7 15 Rc2 e6 16 Rfcl Re8 17 b4!

White Opening System Cliapter l'wo: 'l'lie Stoiiewall

This is an overfinesse, rushing towards doubling heavy pieces on the seventh rank (1 9 Rc7) but apparently overlooking Black's resources. With the simple 18 Nxd4 White would have an excellent garne.

Now 24 Qxa7 allows 24...Ra8! 25 Qxb6, Rxa2 when suddenly it is Black, not White, who has the more dangerous heavy-piece play (and a threat of 26 ...Q $4 27 N@, Ral ch and mates).

28 ~ x a 7 29 Qe4 30 Qd3 31 b5 32 Kf2 33 Kgl 34 Qc4! 35 Nd4

A last bid for complications. There was nothing to be had from 35 ... Bxd4ch 36 Qxd4, Qc5 because the endgame af- ter 37 Qxc5, bxc5 38 Rd7, c4 39 K f l is harmless.

I 38 Kf3 Qhlch

I 39 Kf2 Qxh2ch I 40 Kf3 QhSch? i

Black fails to firid a fine winning idea: 40 ...Q hlch 41 i Kf2, Qelcli 12 Kf3, Kh8! and he wins a piece because 43 ! Nxg7 allows 43 ... Re3ch and mates. i

:; f?!3 43 KPS 44K 3 45 KPS 46 Qc8ch 47 Qc4 48 Qxf7 49 Kf2

Draw

Qhlch Qglch Qdlch Qelch Re6 Re8 Kh8 Qc3ch

Notes to move 6 and 18 show how White should have played to go t;)r the win.

36 Nxf5 d l(Q)ch 37 Kf2 Qelch

White Opening System

CHAPTER THREE

Stonewall I1

4ow let's examine the most common positions that the Stonewall formations. Remember that White need I exactiy in this manner but can back out of the .Il by playing 5 Nf3, reaching one of the true Colle po- le'll consider in succeeding chapters.

t is sometimes believed that the Stonewall was re- ,y the Queen's Gambit (2 c4) once masters began to re- : strength of the latter. Not entirely true: Frank Mar- s one of the few topnotch players before World War I irly resort to 1 d4. And yet after nearly ten years of de- to the Queen's Gambit, the 31-year-old American )n turned to the Stonewall and won some of his nicest i 1908.

Cliapter Ttiree: Stonewall 11 4 5

There is no pasticularly better square for his Knight. It was fashioriable around the tum of the century to play moves such as ... Nbd7 and ...Q c7 early on, but they perform no better than simple development.

For example, Chajes-Capablanca, New York 1911 went 4...Qc7 5 f4, Bg4 6 Nf3, e6 after which White obtained a nice game by getting out of the Kingside pin with 7 QaQch!.

--, . - - -- - Then 7...Qc6?? is a blunder (8 Bb5) and 7...Nc6 makes

8 Ne5 strong. Best, relatively, is 8...Nbd7 8 Ne5, c4 9 Nxg4, Nxg4 and then 10 Be2, Nh6 11 b3! after which Black cannot maintain his chain of light-square pawns and has nothing to show for having given up a Bishop for a Knight. White was clearly better after I l ... cxb3 12 axb3, a6 13 0-0 and 14 c4. See Illustrative Game 4.

This presents a miljor crossroads to Black since he has two reasonable alternatives to our main line of 5...e6. Modem players may feel more comfortable with 5...g6, reaching a po- sition that occurs -- with colors reversed -- in the dutch De- .

fense. The $one.wall Dutch had an undeservedly poor reputa- 11 tion for more than hàlf~a Entury but made a comeback in the ,

late 1980s and early 1990s. - - n a White should theri continue 6 Nf3, Bg7 7 0-0, 0-0 8 Nbd2 and then continue with the tried-arid true attackirig plan

i\ o f Qel-h4 and Ne5. I f Black exchanges pawns on d4. White retakes with hiie-pawn: I-Iis - . .- Queen . . Bishop can be developed at . - ..--.- ~ . ..- I b2 or a3. i? L,?,;;, , i

/ e=" -- i Such positions in the Dutch Defense were once thought

to favor Black because he can eliminate the enemy's good Bishop at what was consijered slight cost by way of 8...Bf5!? 9 Bxf5, gxf5. This judgmcnt now appears suspect, since White can then force the opening of the g-file with 10 Khl, 11 Rgl, 12 Ne5 and eventually g2-g4. White should then stand well.

White Opening System

The other modern approach to the Stonewall is to de- velop Black's Queen Bishop before locking it in with the e- pawn. Here, for example, .Black can~lay&.~Bg4-and if, 6 Nf3, then 6...e6 . An aalys is by'Ludek.Pachrnan in the 1960s rec- ommended 76 i0 , Bd6 8 Qel, 0-0 9 Ne5, Bf5! as favorable to Black, reasoning that 10 BxfS?, exf5 only strengthetis Black's hold on the center.

White can do better with O,Be2, preserving his Bishop and preparing to gain Kingside space wfth . . _ 11 _. -- g4.

', .

Carefully played. By overprotecting e4, White does not allow Blackto establish a double-Stonewall as he Would'after 6' NM, ~ e 4 ! 7 0-0, f5.

++ T u a a s e c o n d bene5t to avoiding 6 Nn.: A genera1 rule of opening strategy is t g k e G ~ u T _ d e v e l o p m e n i f l ~ i b ~ e . Here White sees that his Queen Knight has no better square than d2, so why not put it there immediately? On the other hand, he does not know yet where his other Knight -- or Queen -- belong. Perhaps he will develop the K&g Knight a a 3 and ceserve f3fgrhis Queen or-other Knight. as F a n k Krsha l l d i 7 so effectively iri'tournaments before World War I. See the main line below. C h 3 - q 2

b d i - ~ ~ n e4

This move has a specific posj~iinal threat in mind. Af- ter 7...cxd4 White would not be able to $ay ihe desirab~e 8 exdil hecause of 8...Bxf4. But after 8 cxd4 Black will have suc- ceeded in opening ari entire file - not just half of one. as would occur after 8 exd4 - for his heavy pieces. And it is Black who most iieeds an open Queenside file. White will have enough play as it is on the Kingside thanks to his e5 outpost.

Tlie sarne idea arises after 6...Qc7, as Jose Capablanca played on occasion. Then 7 Ndf3 would open up White's Queen Bishop's diagonal (thereby allowing 7...c.rd4 8 e.xd4!). However, that Knight move has the drawback of permitting 7...NeJ! and 8...fS, with a safe and solid double-Stonewall position. Better for White is 7 Qf3 or 7 Nh3 as in our main cl, %-.-W- -3- -- . - . 1 . lirie.

In Capa's day it was sometimes thought that 6. ..Be7 was siiperior to 6...Bd6, because the latter exposes Black to the dangei. of e3-e4-e5. White can then proceed as in our main line or vai! his plans with 7 Ngf3,O-0 8 0-0. e.g. 8...b6 9 Ne5, Bb7 10 Qf3 followed perhaps by g2-g4-g5 or Qh3.

This has been regarded as strong ever since Marshall's impressive victory over Akiba Rubinstein at Vienna 1908 (see Illustrative Game 5). Now 7...cxd4 8 exd4 only helps White out. as he will be able to use the half-open-e-file to a greater extent than Black will be able use the half-open C-file.

The natura1 move here is 7...0-0 but that is risky be- cause it creates an immediate target for White's pieces. He can then play either 8 g4 or 8 Nh3. For example, 7...0-0 8 Nh3, b6 9 Ng5 and now 9...h6 10 h4, hxg5? only plays into White's hands I I l hxg.5, N-moves 12 Q115 finito). Better is a develop-

48 White Opening System

ment move such as 10 ... Bb7, although White's attack cali con- tinue with 11 g4.

W hite's Middlegame Strategy

From h3 the Knight can go to g5, to take part in the as- sault oXdh7 -and fl, or to fl, where it watches the kzy e4 squares. White is virtucallj-èertain to castle Kingside. but ~vhere will Black castle? On the Queenside it may be just as vulnera- ble to a pawn storm as on the Kingside (see Marshall-Rubin- stein below).

And the other question of pertinence is this: Who will open lines and how? - If Black - . . , - H . castles Kingside, White necd not change the pawn strutture, but cari-continue with norma1 at- tacking ideas -435 followed by Qh.5). If ---- Black remains . in thg.-xnt_er-or castles (iieensid5,- . . - . . -. ... White will push his e-pawn: Black's counte@lay,-however, is not at al1 apparent. See Gamk 5 for an illustration of competing strategies.

Chapter Three: Stonewall I1 49

Illustrative Games

(4) CHA JES-CAPABLANCA New York 1911

It's important for White to challenge Black's impendin Oueenside e x p ~ s j o ~ (from ... a7-a6 and then ... b7-b5) and als5 to provide a means of 'openinglines. Witliin-Tive-moves it is White - not Black - who has expanded on the Queenside and owns more terrain there. Notice that without his light-squared Bishop, Black cannot easily maintain pawns on squares such as c4.

Il... cxb3 12 axb3 a6 13 0-0 Bd6 . 14 c4 0-0 15 c5!

50 White Opening System

White avoids the cornplications of 15 Nc3, b5 ( I6 cxbS?. Q.rc3) and also prepares a Queenside pawn storin wiih b3-b4-b5. To avoid that. Black must advance his own b-paw~i. thereby creating a game-long wecikness at a6. In short, White is in control.

White dreams of having time for 23 ... Rfa8 24 Rla3 followed by 25 Qa2 and 26 BxbS!. But his Rooks are now pushed back and it was tirne for White to realize that he need.; a second enerny weakness in order to win this garne. Therefore. it was tirne to begin looking at preparations for g2-g4.. As thr: garne goes, Black gets the g-pawn idea first.

23 ... Rfa8 24 h3 Bd8 25 R5a3 g5 26 g3 Kh8 27 Kh2 28 Rgl 29 Qd1

2k7 30 Be2

Rg8 Qe7

Black has done his best to seal off the Queenside antl direct both players' attention to the g-file.

31 Q a l 32 Rcl

Qb7 gxf4

33 gxf4 Raa8 34 Rgl 35 Qxgl Ng

Chapter Three: Stonewall TI

36 Bh5 Ne7 37 Ra2 38 Qfl

Rg8 Nc6

39 Bel! Ra8 40 ~ d l Qe7 41 Rg2

Inevitably, with only one file open, the remaining heavy pieces will be traded off - since neither player can allow the other uncontested control of the file for very long. That rneans an endgame will be reached in which White has two Bishops versus a Bishop-and-Knight, and also has the advan- tage of a passed C-pawn. Despite his bad dark-squared Bishop, he has good, perhaps excellent, winning chances.

41 ... 42 Bd2!? 43 Qf3 44 Be2 45 Qxg2 46 Bf3 47 Bh5

49 48 K22 K 50 Ke2 51 Bf3 52 K f l 53 Ke2 54 Bh5

White Opening System I Chapter Three: Stonewall I1 53

White's problem is that his King has no means of pene- tration, since g3, g4 and h5 are sealed off by Black's minor pieces and f-pawn. That means he will have to distract Black's King and pieces in some way. He has two resources to Liccom- plish that - attacking e6 and advancing the C-pawn. Right now Black's King covers both c6 and e6 - and also threatens to trap a Bishop with 56 ... Ke7!.

56 c6ch! Kxc6 57 Bxe6 Ne4 58 Bel Bxel 59 Kxel Nc3 60 Bxf5 h6

White has won a pawn temporarily but his b-piiwn is doomed. Chajes forces a draw now.

Not 63 e5, Nd3ch! and Black calls the tune.

Draw.

Neither side can make progress. White's King cannot leave the vicinity of c2, or the a-pawn will Queen. And 69 Kb2, Kd6 70 Kc2, Ke7 (which threatens 71 ... Kf6 and 72 ... Kd5) only allows White to advance with 71 d5, Kf6 72 d6!. White should have gotten in g4 first as pointed out at nove 23.

(5) MARSHALL-RUBINSTEIN Vienna 1908

Black carefully avoids committing his King and begins preparations for ... 0-0-0. Note how useful White's next move is. From f2 the Knight (a) protects a Bishop, (b) helps keep en- emy Knights off e4, (C) prepares to push the e-pawn, and (d) watches g4, a key square in case Black castles short.

9 Nf2! 0-0-0

White Opening System

Because of the threat of 13 e5, forking two pieces. Black must liquidate the center in White's favor and losr time with his Bishop.

Black cannot win a pawn because of the attack cln the d6-Bishop.

This signals the beginning of a genera1 Queenside ad- vance. The ultimate goal is the opening of a Queenside file for White's heavy pieces. The interim method of achieving that goal will be harassing Black's Queen with pieces and pawnb.

17 ... Ne7 18 b4 19 Bd4

Qc7 f6

20 Qf2 Nc8 21 Rfel!

l Chapter Three: Stonewall I1 55

An important move. Black had to play his 19th move to avert 20 Be5. However, the pawn move had a secondary pur- pose. He hoped to drive White back with a well-timed ... e6-e5. Now that chance is halted.

Black cannot contro1 the Queenside files any longer. Naturally, 25 ... axb6 26 axb6, Nxb6 will be punished (not by

i 2 7 Bxb6, since 2 7 ...Q xb6 is a check) but by solid attacking I moves such as 27 Rfbl . ...

!

A fine continuing stroke to maintain the attack. Two pawns up. White could win in a variety of manners, but he prefers the tactical one (e.g. 2 9 ... Nxd4 30 Qe5ch, Ka8 21 uxb7ch, etc.).

29 ... axb6 30 QeSch Ka8 31 axb7ch Kxb7 32 Bf2 Rd5 33 Qf6 34 Rebl

Qc6 Rb5

35 Rxb5 Qxb5 36 QBch!

After this White wins a third pawn forces an endgame. Black could safely have resigned without missing much, but he bets on his advanced King being worth com- pensation.

White Opening System

37 Qg8 38 Qxe8 39 Rbl 40 Rxb6ch 41 g3 42 RbSch 43 Kg2 44 Re5ch 45 4 46 f5 47 Bd4

Avoiding the fina1 trap (48 Rxeo??, Nf4ch).

48 ... exf5 49 RxfS Rg6 50 Rf7 h5 51 Rg7! Rxg7 52 Bxg7 hxg4 53 Kxg4! Nxd 54 Bxc3

Black Resigns.

Even without 53 ... Nxc3 there was no way to stop the h- pawn.

Chapter Four: The Basic Colle

CHAPTER FOUR

The Basic Colle

In this chapter we'll examine the basic choices con- fronting Black in the Colle, leaving the main lines for Chapter Five.

Again 4. ..e6 would block in Black's Queen Bishop and allow whj&,qgood choicf;. He could continue as in the line that follows with our basic Mode1 Development a la Col1 or he could convert the position into a Stonewall with d Nf'3. A ruieof.iliumb: if ~lacEfZF~?.i;è6;thihk strongly about fl the Stonewall Attack.

----___ -2- . ..- 'I W:.--

-- P

There are some slight differences between 4...Nc6 and 4...Nbd7, but they should not trouble White much. With the Knight on d7, Black can contro1 the b7-e4 diagonal better with a subsequent fianchetto of his Queen Bishop. He is also better prepared to meet dxc5 since ... Nxc5! will attack White's Bishop on d3 and blunt any attack. That also means that when White inevitably breaks in the center with e3-e4, Black will be