Mexico city: first blood in round 2

Blood and excitement, at last! After four boring (in my opinion) draws in round 1, the World chess championship saw some really amazing games in round 2. Only Gelfand and Grischuk decided to share the point after 23 moves. In the remaining games, Vishy Anand outplayed Levon Aronian with Black pieces after a complicated and thrilling middlegame, where the Armenian #1 made the last mistake; Vladimir Kramnik, White, sacrificed a piece against his compatriot Alexander Morozevich and soon got some initiative, Black didn't find the better defence and made a terrible and decisive blunder in severe time pressure; Svidler pushed for a win after gaining a pawn on move 33, but he soon realised that he had nothing more than a draw, which was agreed ten moves later. I really appreciated the fight spirit of all participants in this round (all but Gelfand and Grischuk: their position was about equal, but still playable) and I hope we will see more interesting battles in round 3, where Anand and Kramnik, who share the lead on 1.5/2, will play each other. The official site of the competition is http://www.chessmexico.com/; you can also fine results and download/reply games on my Italian site, www.messaggeroscacchi.it (link to the WCC page is http://www.messaggeroscacchi.it/mondo/mondiale07.html).
And now here are some annotations to the exciting Kramnik-Morozevich game...

Kramnik,V (2769) - Morozevich,A (2758) [E04], Mexico City 14.9.2007
1.Nf3 Nf6 2.c4 e6 3.g3 d5 4.d4
Catalan system, one of Kramnik's favorites.
4...dxc4 5.Bg2 a6 6.Ne5 Bb4+ 7.Nc3 Nd5 8.0–0!?
I could be wrong, but this sacrifice looks to be a new idea. 8.Bd2 is the most common reply, while 8.Qc2 has been played a few times.
8...0–0
After 8...Nxc3 9.bxc3 Bxc3 10.Rb1 Qxd4 11.Qxd4 Bxd4 12.Nxc4 White has full compensation for the sacrificed pawns. 8...Bxc3 9.e4! Bxb2 10.Bxb2 Nb6 11.Rc1 is ok for White as well.
9.Qc2 b5 10.Nxd5 exd5 11.b3 c6 12.e4!
After logical and positional moves by both sides, Kramnik decides to sacrifice a piece (home preparation, I guess). 12.bxc4 bxc4 (12...dxc4 13.Rd1 gives White enough compensation) 13.e4 was less risky, e.g.: 13...a5 (13...f6? 14.Nxc4) 14.exd5 cxd5 15.a3 Be7 16.Rb1 Be6 17.Nxc4 Nc6 with an equal game.
12...f6 13.exd5
13.Nf3 dxe4 14.Qxe4 Re8 15.Qc2 Be6 looks good only for Black.
13...fxe5 14.bxc4 exd4 15.dxc6 Be6
Black must be careful. After 15...Ra7 16.Qb3 Bc3 (16...Bc5 17.cxb5+ Kh8 18.b6 Qxb6 19.Qxb6 Bxb6 20.Rb1 Bc7 21.Ba3 Rg8 22.Bc5 Ra8 23.Bxd4 and Black is paralysed) 17.cxb5+ Raf7 (17...Kh8 18.b6 wins) 18.b6 Nxc6 (18...Qf6 19.c7 Be6 20.Qa3! Bxa1 21.Bf4 Bc4 22.Rxa1 Qxb6 23.Rc1 with good winning chances) 19.Bxc6 Bxa1 20.Ba3 Qf6 21.Bd5 Bc3 22.b7 Bxb7 23.Qxb7 and White has some initiative.
16.cxb5
White tries to keep the position as much complicated as possible. 16.c7 Qxc7 17.Bxa8 Qxc4 18.Qxc4 Bxc4 19.Bf4 Nd7 is good for Black.
16...d3?
First inaccuracy. 16...Ra7 looks more precise, although after 17.Rb1 d3 (17...Ba5 18.Be4 Kh8 19.Ba3 Re8 20.Bc5 Rc7 21.Qa4 and White is at least slightly better) 18.Qb2 d2 19.Bxd2 Bxd2 (19...Qxd2 20.b6+-) 20.b6 Raf7 21.Rbd1 Nxc6 22.Rxd2 Rd7 23.Rfd1 Nb8 24.b7 Rxd2 25.Rxd2 White has more than enough compensation for the piece.
17.c7! Qd4
17...dxc2 was a practical alternative to be considered: after 18.cxd8Q Rxd8 19.Bxa8 axb5 20.Be4 Rc8 White has winning chances, but Black can fight.; 17...Qd6 was not much better than the text move: 18.Qb2 (18.Qa4 Nd7 19.Bxa8 Nb6 20.Qxa6 d2 21.Bxd2 Bxd2 22.Bg2 Qxc7 and Black has good drawing chances) 18...Nd7 19.Bxa8 Rxa8 20.Bf4 Qf8 21.Rfd1 with excellent winning chances for White.
18.Qa4 Nd7 19.Be3 Qd6 20.Bxa8 Rxa8 21.Bf4?
A serious mistake. After 21.Qxa6! Qxa6 22.bxa6 Bd6 23.Rac1 White has an almost decisive advantage.
21...Qf8??
A blunder made in severe time trouble. 21...Qd5 was the only way to survive, although after 22.bxa6 (22.Rac1 also deserves attention) 22...Qf3 23.Qd1 Qe4 24.Rb1 Bh3 25.f3 Qd4+ 26.Kh1 Bxf1 27.Qxf1 White retains some winning chances.
22.b6 Ne5
Desperation. 22...Nxb6 23.Qc6 Bd5 24.Qxb6 a5 25.Qd4 wins anyway.
23.Bxe5
23.b7 Nf3+ 24.Kh1 Bd5 25.Qxb4! Nd2+ 26.f3 is even stronger.
23...Qf3 24.Qd1 Qe4 25.b7 Rf8
25...Qxb7 26.Qxd3 Bh3 27.f3 is hopeless anyway, but the text move loses on the spot.
26.c8Q Bd5
26...Rxc8 27.bxc8Q+ Bxc8 28.Qb3++-
27.f3 1–0