Monday, May 24, 2010

US Chess Championship 2010: Joel Benjamin v. Alex Onischuk

Joel Benjamin v. Alex Onischuk



1. e4

A standard move that generally allows for White's fast development.

1...e5


Black responds symmetrically and will hope to keep up with White.

2. Nf3

White attacks Black's e5 pawn, while developing his Kingside.

2...Nc6

Black defends the e5 pawn while developing his Queen side.

3. Bb5


White attacks Black's Knight, which is the only defender of the e5 pawn. White has also completed his Kingside development and can castle Kingside whenever he wants too. This opening is very common and old, and is called the Ruy Lopez, I believe after a Spanish chess player from the 1600s or 1700s.

3...a6

Black pushes back the bishop, or encourages the exchange of White's Bishop for Black's Knight. That variation, called the exchange variation, is very complicated and interesting, but as this does not happen here, I wont go into the reasons why Black is not afraid of losing his e pawn after 4. Bxc6 dxc6 5. Nxe5.

4. Ba4

White, having decided not to exchange his Light Squared Bishop for Black's c6 Knight, has to move the Light Squared Bishop. Moving it to this square allows White to retain the possibility of Bxc6-dxc6-Nxe5, so Black must play his moves with this tactic in mind.

4...Nf6


One way Black can deal with the threat against his e5 pawn is by directly defending it. A move like Bd6 or d6 would ensure Black that he does not lose his e5 pawn. These moves will give Black other problems, though, especially with regard to the harmonious development of his pieces. The other way Black can deal with White's attack on his e5 pawn is by counter attacking, which is what he does here with the move Nf6. White can win Black's e5 pawn, but Black will be able to win White's e4 pawn.

5. 0-0

White in turn does not directly defend his e4 pawn, but instead defends it with a tactic. If 5...Nxe4 then 6. Re1 Nd6 7. Nxe5 and Black has some difficulties developing his Queen side. By Castling, White gets his king to safety and can now begin more drastic attacking measures without as much fear of counter attacks.

5...Be7

By blocking the e file with his Bishop, and by allowing himself to castle King side in one move, Black makes his threat against the e4 pawn much better. White's counterattack down the e file would not be nearly as strong.

6. Bxc6

But Black's move allows this, and White can win Black's e5 pawn. This is often times called the delayed Exchange Variation. I am not as familiar with this type of variation as I am with the normal exchange variation, so I can only guess as to the reasons for the delay. I would guess that White likes to wait and see what Black will do, and depending on Black's moves he will either prefer the exchange variations, or the more normal Ruy Lopez variation. For myself, I would probably aim to play Bc5 as Black in the Exchange variation, so maybe since the Bishop has moved to e7, White is more comfortable with the exchange variation.

6...dxc6



Black wants to complete his development and maintain a somewhat solid pawn structure. bxc6 is possible, but Black's queen side pawns and slow development can give White a good game.

7. Nc3

White has eliminated Black's defender of the e5 pawn, but before taking it he defends his on e4 pawn.

7...Nd7

As White has defended his e4 pawn, Black decides to remove his attacker of that pawn and instead defend his e5 pawn.

8. d4

White has developed all he can without a central pawn push or a fianchettoing of his Dark Squared Bishop. d3 is fairly passive, and b3 doesnt make a whole lot of sense in this position. Therefore, the d4 pawn push is appropriate.

8...exd4

John Watson, in his book Chess Strategy in Action, has a whole chapter devoted to how rare surrendering the center like this is in Modern Chess. Maybe Black could do well by playing 8...Bd6? After exchanges on e5, 9. dxe5 Nxe5 10. Nxe5 Bxe5 11. Qxd8+ the position is reminiscent of the Berlin Defense. In fact, this position is in some ways better than the normal Berlin Defense, as a pair of Knights has been traded off. This generally increases the safety and power of Black's bishop pair.

Surrendering the center like this does open up the position a bit though. If Black is confident he can get his Bishop pair developed before White can do him any harm, than it makes sense for Black to want to open up the center.

9. Qxd4



White takes back the pawn with the Queen. It is difficult for Black to harass the White Queen, so it is not especially bad that she has moved to the center like this. The Queen is also attacking g7.

9...0-0

Black gets his King to safety and protects the g7 pawn. His position is still fairly cramped though, and the Light Squared Bishop and Queen side rook are particular bothersome at this point.

10. Rd1

White increases his pressure down the d file. Unfortunately for him, this pressure is somewhat ephemeral.

10...Nc5

Black has just enough protection on his d8 square to perform this maneuver. His Light Squared Bishop's prospects look much better now.

11. Qe3



White moves his Queen so his d1 rook forces the Black Queen to e8.

11...Qe8

Black has to move his Queen out of the d1 Rooks line of fire

12. Nd4

White centralizes his Knight. The Knight is hitting the e6 square, which hinders Black's development a bit. The Knight is also threatening to go to f5, where it his the vulnerable squares g7, e7, and h6. The Knight may want to reroute itself via the e2 square, but it seems doubtful this plan will be successful.

12...Bd6

Black is starting to get some harmony in his position. The Dark Squared Bishop gets out of the Queen's way on the e file, protects the important e5 square, and also looks menacingly at the h2 square. The Light Squared Bishop and Dark Squared Bishop are looking pretty good along there respective diagonals, taking control over a whole slew of King side squares.

13. Qf3



This is sort of a strange move. I am not sure if it has any specific and most important point. I can spot a lot of little things it does though. First, the Queen gets out of the way of White's Dark Squared Bishop. Now, the Bishop is able to go to e3, f4, or g5. Second, the Queen takes the g4 square, which prevents an annoying Bg4. White doesnt really want to weaken his King side with f3, but he also doesnt want to have to move his Rook off the d1 square, where it may become vulnerable to other tactics. Third, the Queen supports the d4 Knights move to the f5 square. Finally, the Queen can get to the h5 square, where it may be able to harass the Black King side a bit.

13...Qe5

By contrast, this move has a fairly straight forward purpose, and that is to threaten h2! The Queen also puts some pressure on the d4 Knight, takes away the h5 square from the White Queen, and protects the f5 square a bit.

14. g3

White has to defend against the threaten against h2. Qg3 isnt so good because White's King side pawn structure will get messed up.

14...Ne6

The Black Knight attacks White's d4 Knight. The Black Knight also takes control of the f4 and g5 squares.

15. Nf5



The White Knight needs to be defended or move from d4, and White chooses to move the Knight to f5. From f5, the Knight can hit e7 with check. The Knight is also putting pressure on the g7 pawn. Finally, the Knight is able to move to the e3 square where it can defend a lot of the Light Squares.

15...Re8

Black places his Rook on the e file, where it defends e7, and can potentially unleash an attack against White's e4 pawn.

16. Be3

White wants to develop his rooks, and he first must move his Bishop somewhere. On e3 the Bishop takes control of the d4 and c5 squares, while maintaining control over the f4 g5 and h6 squares. Nxd6 doesnt seem as promising because, though White can get rid of Black's Bishop pair, Black's pawns would be undoubled in the process. Further, White would be left with a Dark Squared Bishop, and Black would have a Light Squared Bishop, which increases the chances of an opposite colored bishop ending, which are draws in all but a few circumstances.

16...Bf8



Well, the purpose of this move alludes me a bit. On the one hand, it doesnt hurt Black's position at all. It protects g7 a bit. Finally, it gets the Bishop out of White's Knight's grasp.

Actually, reflecting on this move after going through some of the later moves, it is much clearer what this moves purpose is. This move protects against back rank mates. Blacks plan is to attack White's e4 pawn, which he will achieve eventually by Ng5.

17. Rd3

White aims to double his rooks on the d file. The d file is the only open file on the board, so this should lead to a nice advantage for White. However, Black's minor pieces and doubled c pawns do a nice job of defending possible invasion squares, so in reality White's doubling of his rooks does not achieve a whole lot.

17...f6

This move takes control of the g5 square, where Black plans to move his Knight next. This will either win the e4 pawn, or will force White to exchange off his Dark Squared Bishop. Either way, this works out well for Black.

18. Rad1

White has doubled his Rooks on the d file, but as noted on his 17th move, to what end are they doubled?

18...Ng5



Black's plan of attack on the e4 pawn is complete.

19. Bxg5

White is forced to give up his last bishop for Black's Knight. This gives Black a nice advantage going into many end games. The fact that his g pawns are now doubled is not all that important, as White had a King Side pawn majority anyway. Thus, Black's King side pawns are not going to be thinking about advancing, so much as they will be used for stalling or attacking White's pawn majority.

19...fxg5

Forced

20. Rd8



White invades on the only possible square d8. This allows him to simplify in a somewhat decent endgame. He may have underestimated Black's resources in the endgame though.

20...Bxf5

Finally Black develops his Light Squared Bishop, and now things simplify in a more or less forced way.

21. Rxa8 Rxa8

22. Qxf5 Bd6

Black prefers to have his Bishop on e5 than to have White get doubled f pawns.

23. Qxe5 Bxe5

24. Rd7



White has achieved the fruits of his d file control. Unfortunately, though, Black's c7 and g7 pawns are firmly defended by Black's Dark Squared Bishop.

24...Re8

Black does not want White to harass his Dark Squared Bishop by Re7. This move also moderately threatens Bxc3 and then Rxe4.

25. f3

White defends his e4 pawn.

25...g4



Black attempts to undermine White's defense of his e4 pawn.

26. Kf2

Rather than playing fxg4 and having doubled pawns on the g file, White gets his King to the Center as fast as possible.

26...gxf3

Black undermines the defense of the e4 pawn.

27. Kxf3

White retakes the f3 pawn, brings his King closer to the center and provides some defense for the e4 pawn.

27...Re6



Black prepares his Rook for possible King side action.

28. Ne2

White takes advantage of his attack on the c7 pawn to reroute his Knight to a better spot. Taking the b2 pawn for Black is not so good because White can take his c7 pawn, and his b7 pawn will be vulnerable. If Black plays, say b6, then his a6 and c6 pawns will be vulnerable.

28...Kf8

Black begins to move his King to the center. The first order of business for Black is to get the Rook off of d7. This move also protects the important e7 square.

29. Nf4



White brings his Knight to an aggressive square where it can harass the Black Rook.

29...Rf6

Black pins the Knight to the King while getting his rook out of harms way.

30. h4

Black is threatening g5, when the pinned Knight is lost. This is one way to parry this threat. Maybe moving the King right away would have been better though. On the one hand, White wants to advance his King side pawns to help with his promotion of either the e pawn or a King side pawn. However, this move undermines some of the solidness of White's pawn structure.

30...Ke8

The Black King is free to leave the g7 pawn undefended, as Rxg7 is met by Rxf4+ and then Bxg7. The King is able to evict the White rook.

31. Rd1

White has to retreat his rook, and now if Bxb2 White can counter with Rb1 and win the b7 pawn.

31...Rd6



Black fights for control of the d file. White really cant take here, because that would undouble Black's pawns.

32. Nd3

White moves his Knight in such a way as to protect the b2 pawn and prevent the exchange of rooks. The mild threat of Nxe5 is also created, but White cannot do this at the moment because his Rook on d1 is unprotected.

32...Ke7

Black takes advantage of White's lack of attacking resources at the moment to centralize his King. Black is in pretty good control of the situation at this point, though it is still difficult for him to think about winning the endgame because his Queen side pawn majority is not a real majority. This is the primary place where the doubled c pawns can be seen for the weaknesses that they are. Black is unable to create a passed pawn on the Queen side, which makes any winning plans difficult to achieve.

33. Re1



White takes the time to get out of the fire of Black's Rook. This move also supports the e pawn, which is critical to White's game. White is still in good shape, though it is looking more and more like he should be content with a draw.

33...Ke6

Black centralizes his King some more, and moves towards the critical e4 pawn.

34. b3

White takes the time to get his b2 pawn out of danger. Now his Knight is free to move about.

34...b6

Black works to try and get his Queen Side Pawn Majority rolling. As noted above, those c pawns are really hindering his progress. However, the move b3 allows Black the fairly straightforward plan of c5-c4 and then he can exchange off one of his doubled c pawns for either White's a or c pawn. This would give Black a true Queen side pawn majority, and his winning chances would increase quite a bit.

35. g4

White wants to get some space on the King side, as well as getting the g pawn out of the reach of Black's Dark squared Bishop. White can move his King to e3, and then move his Rook to f7 where it can counter Black's control of the d file.

35...c5



Black aims to trade off his doubled pawn, while at the same time taking some central control as well.

36. Ke3

White moves his King to the e file, so as to open up the f file for his rook.

36...Bc5+

Black gets his bishop into position to defend the c5 square, as well as harass the White King for a tempo.

37. Ke2

White has to move his King and does not want to move it to the f file.

37...c4

Black sacrifices a pawn to destroy White's Queen side pawn structure. This sacrifice can almost not even be considered a sacrifice, as the pawn is doubled, and White will have a difficult if not impossible time holding on to his pawns if they are on a2, c2 and c4.

38. bxc4



White is in a bit of bad shape at the moment. He doesnt want to allow cxb3, but bxc4 isnt all that great either. There are some tactics that White was probably hoping would save his game.

38...Rc6

Black immediately attacks the weak c4 pawn. White can perhaps take joy that Black's rook has abandoned control of the d file, but it is not a great joy. The computer recommends 39. Rb1, so that after 39...Rxc4 White can play 40. Rb4 Rxb4 41. Nxb4 and White can get to a less scary Knight and Bishop endgame.

39. c5

White hopes to use some tactics to get out of his bind. Unfortunately for him, they do not appear to be correct.

39...Bxc5

Black takes the pawn without messing up his pawn structure.

40. Rf1



White gets his rook to the f file, where he hopes he can counter attack sufficiently to make up for Black's progress on the Queen Side.

40...Be7

Black gets his Bishop out of the attack of the Knight and also unleashes his Rook on the c2 pawn. Capture of the c pawn comes with Check, so White must be especially careful.

41. Nf4+

White tries to get out of his bind first with this check and then an attack on Black's Bishop.

41...Ke5

Black's King gets further into the fray, and is now attacking the undefended e4 pawn.

42. Nd5



White completes his maneuver and attacks the Bishop on e7. Notably, Black is now attacking three of White's pawns!

42...Bxh4

Black takes the pawn that doesnt lose him a bishop.

43. Kd3

If the c pawn would be taken without check, then maybe Rh1, forcing the loss of the h7 pawn or g5, which blocks the Bishop somewhat out of play would help White maintain the balance. However, the c pawn would be taken with check, so White must defend it with his King. He also defends the e4 pawn.

43...Rd6



Black pins the Knight against the King and threatens c6, winning the Knight.

44. Rf8

A nice tactical move in a difficult position. White parries the threat of c6 by threatening Re8+. If 44...c6 then 45. Re8+ Re6 (the only move) 46. Rxe6+ Kxe6 and the Knight can take the b6 pawn.

44...Rd8

Black has made sufficient progress in the position that he can trade off the rooks and win the Bishop vs Knight endgame. Notice that the c7 pawn would be defended if 45. Rxd8 Bxd8.

45. Rf5+

White wants to keep the rook on, so he can make as many threats as possible. It is important to keep on attacking when you are in a bad endgame.

45...Ke6

Kd6 would block the Rook's pressure down the d file.

46. Ke3



White unpins his Knight.

46...Bg3

Now that White's Knight is not pinned, Black has to defend his c7 pawn. This bishop move also gets the Bishop more into the game.

47. Rh5

White counter attacks down the h file.

47...h6



Black has to defend the h7 pawn, and pushing it is preferable to placing his rook in the passive position by Rh8.

48. g5

White continues his assault on the Black King side. If he can win those two King side pawns for his one King side pawn, he would be in good shape to fight for a draw.

48...Rh8



Now the Black rook is forced to this square. 48...hxg5 49. Rxg5 and White has a good chance to capture the g pawn or cause Black other problems.

49. Nf4+

If 49. gxh6 Rxh6 Black has a good position.

49...Bxf4+

Black is happy to exchange off the Knight.

50. Kxf4



Forced.

50...Kf7

The Black King goes to the defense of his King side pawns.

51. Ke5

The White King tries to help promote his e pawn. He might have been better off trading off one of Black's King side pawns.

51...Kg6



Now Black can win White's h pawn and not lose either of his King side pawns.

52. Rh2

White has to retreat the rook.

52...Re8+

Before taking the g5 pawn, Black wants to get his rook in a good spot to stop the e pawn from promoting.

53. Kd5



White has to move his King.

53...Kxg5

Black now takes the g5 pawn.

54. e5

White has to try and promote his e pawn.

54...h5

Black has to counter by trying to promote his h pawn.

55. e6 h4



If White plays 56. Rg2+ trying to win the g pawn, than 56...Kh6 57. Rg4 g5 and White has only wasted time.

56. Ke5

The White King wants to keep the Black King away from the e pawn. White will try and get his Rook down the f file or d file and try and promote the e pawn.

56...Kh5

Black prepares g5.

57. Rf2



White prepares to use his Rook to promote his e pawn.

57...h3

Black counters by pushing his pawn.

58. Rf3

White wants to harass the pawn while not giving up the f file.

58...Kg4

Black attacks the Rook and also prepares to aid the h pawn to its destiny.

59. Rf7



Preparing Rxg7+ or e7.

59...g5

Black does not want to give up this pawn for no real reason.

60. Kf6

The White King can finally get in, but Black's pawns are close to promotion.

60...Rh8



Black can trade off his rook for the e pawn if necessary and promote his h pawn anyway. If 61. e7 h2 62. Rf8 h1=Q 63. e8=Q Rxf8+ 64. Qxf8 Qf3+ and after the Queen's are traded, White cannot stop Black's g pawn from promoting.

61. e7 h2

62. Rh7

White has a last ditch effort to try and get a Queen and then a perpetual check.

62...Rxh7

63. e8=Q h1=Q



64. Qe6+ Kh4



And here White resigns. The Black King will be safe from checks and Black is up a Rook and two pawns.

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