Chess is life--every move a person makes has consequences, as in the following position:

The more actively one plays, the more one can get an advantage. It is easy to squander all of one's resources on a risky gambit, but it is also dangerous to play defensively while giving an opponent an opportunity to attack. The game that we will analyze today is from Alexander Morozevich, a very aggressive player with an unorthodox playing style.Morozevich,A (2755) - Sakaev,K (2634) [D10]

60th ch-RUS Superfinal Moscow RUS (5), 23.12.2007

1.d4 d5  A decision by Morozevich to play a closed game rather than beginning with the tactical e4

2.c4 c6 

3.Nc3 Nf6

4.cxd5 cxd5  D10 Queen's Gambit Declined Slav Defense

5.Bf4 Nc6  White's dark squared bishop can also develop to Bg5 here

6.e3 a6

7.Rc1 Bg4

A very odd move by Sakaev, perhaps designed to upset Morozevich's preparation

8.f3 Bd7  Black purposely loses a tempo here, which is not a good idea because Black must seek to equalize

9.g4 e6  Morozevich plays his usual tactical style

10.h4 Be7  Chess Genius evaluates this position as good for black, perhaps because of white's weakened kingside pawn structure

11.Bd3 0-0  Sakaev decides to castle into a dangerous position with white preparing a kingside attack

WHITE TO MOVE

12.Bb1 Qb6  The b2 pawn is hanging, but white has a tremendous positional advantage

13.Rh2 Rfc8

14.h5 Be8

15.Qd3 Nb4 Morozevich's pieces are ready to leap into action

16.Qd2 Nd7  Sakaev prepares a queenside attack, and a Sicilian Defense position develops in which white is attacking on the kingside and black on the queenside

17.Nh3 Nf8  The computer imagines that h6 is the best next move for white

18.Bg5 Qd8

19.Bxe7 Qxe7 After these moves, Chess Genius evaluates this position as a slight advantage for White

20.f4 f6

21.Kf2 Qd6 There is no obvious plan for black, while white is just poised to spring an attack on the kingside

22.Ng1 Rc7

23.Nf3 Rac8 Sakaev formulates a strategic plan to attack

24.h6 g6

25.a3 Nc6

26.e4 Qd8

27.Ba2 Ne7

28.e5 f5

29.Rg1 Rc6

30.Bb1 Kh8 This position is already evaluated by Chess Genius as extremely dangerous for Black. Black's pieces have nowhere to go and Morozevich is gradually increasing the tension on the kingside

31.Rhg2 fxg4

32.Rxg4 Bf7

33.Ne2 Nd7

34.Ng5 Bg8  After all of these moves, Sakaev (Black) has little counterplay. This is the type of tactical game Morozevich enjoys.

35.R4g3 Nb6

36.b3 Qf8

37.a4 Nd7

38.a5 R6c7

39.Rf3 Nb8

40.b4 Nbc6

41.Rc1 Qxh6 Interesting, the queen takes the pawn, but the position is critical with white threatening Rh3, Rh1, etc.

42.Rh3 Qf8

43.f5 Nxf5 Now the computer imagines Black is winning by at least two pawns

44.Nf4 Qe8 

45.Bxf5 exf5

46.Rc5 Rd8

47.Qe3 h5

48.e6 Re7? Is this a questionable move or the only move?

49.Rxc6! bxc6

50.Qe5+ Rg7 The computer suggests Nf7+ leading to a draw instead of Qe5

51.Qf6? (51.Rg3 delivers mate) Qf6 may even be losing with the proper defense

51...Rb8

52.e7 Bh7 Morozovich wins the game because he has effectively sacrificed the exchange in order to gain a positional advantage

53.Re3 Kg8

54.Qe6+ Kh8 Chess Genius imagines a threefold repetition here with Qf6

55.Qf6 Kg8 

56.Qe6+ Kh8

57.Qd6 Ra8

58.Qc7 Rg8 The computer falsely predicts that white has a losing position, but after Qc7, the position is complex

59.Nfe6 1-0.  Sakaev resigns, but is the position really losing for black?

After Qb8, e8=Q , Qxc7, Qxg8, Kxg8, Nxc7, white has a winning position because of its better positioned pieces. While there appears to be equality, Sakaev cannot defend the a6 pawn and the rook simultaneously.  Rb8 Nxa6 defends the white b4 pawn.

As we can see, this was an exciting game with a great deal of tension on the kingside that Morozevich obtained. He sacrificed the exchange with the white rook taking the knight on C6 in order to gain a positional advantage that most patzers like myself would not dare to do against another grandmaster. At such a high level, an exchange sacrifice like this must be well thought out because sacrificing the exchange can be risky if one does not gain a positional advantage after a loss of material.

Now, why did Morozevich feel the sacrifice was justified? Most likely because by sacrificing the exchange, he was able to advance the e7 pawn and remove a defender. The Knight on C6 would stop the e7 pawn from moving forward. One does not have to be a computer to understand the positional advantage one gains by such a move.  Once the white pawn advanced to e7, the passed pawn increased in value and made the position very complicated for black. 

Interestingly, Chess Genius did not see white's advantage after the exchange sacrifice, most likely because it did not understand the value of strategic thinking. Of course, this is a computer program running on a mobile phone, but it does have a US Chess Federation rating of around 2500.  For instance, Chess Genius spotted the continuation

54. Qe6+ Kh8

WHITE TO MOVE

55. Qe5 (instead of Qf6 as played in the game) Kg8

56. Qxb8 Rxe7

57. Qxe8+  Rxe8

58. Rxe8+

with a tremendous advantage for white. Morozevich did not play this continuation however in the game.

Instead, he opted for the quieter variation 56. Qf6, which Chess Genius imagines as equal with proper defensive play from Black.

However, it is clear that Morozevich had the active and winning position.

One must understand that even grandmasters cannot spot all of the possible variations in a chess game.