ODT130611

=**Karjakin ends Carlsen's run**=




 * Problem:** Black to play and mate in 4.

World number one, Magnus Carlsen's string of tournament victories was finally brought to an end in his home country of Norway. The inaugural Norway Supreme Masters tournament, inspired by Carlsens success, attracted an immensely strong field of ten players, including seven of the top ten players in the world.

The event was set alight by the sprint start of four straight victories by Sergey Karjarkin of Russia, opening up a 1½ point gap on the field. Karjarkin's run was halted by Carlsen in round 5, recording his first win in the tournament. Carlsen closed the gap to half a point in the following round, but Karjarkin managed to keep that distance to the end of the tournament, winning with a score of 6/9. Carlsen and US grandmaster Hikaru Nakamura finished in a tie for second on 5½.

Today's game features Karjakin with the black pieces in round four against world number two Lev Aronian of Armenia. media type="custom" key="25053892" This check and retreat is all part of the Queen's Indian Nimzovich variation. Having played b2-b3, the white bishop is not so well placed on d2. Until this move the game had been following Hammer-Karjarkin from round 2. Unfortunately for Aronian, he couldn't quite remember what to play after his prepared improvement. Instead 21... Rc7? runs into tactics: 22 Nxf7! Rxf7 23 Bxc7 Qxc7 24 Be6 winning two rooks and a pawn for three pieces. More dynamic than 23... g6 with a solid position. Black is offering to change the blocked central pawn structure – giving both sides a passed pawn. White accepts, though 24 Bxe5 with an equal game was safer. Here 25 Rxc1 Nc4 26 Bxf5 is highly complex, for instance: 26.--- Rxf5!? 27 Qxf5 g5 appearing to win two bishops for rook and pawn, but 28 Rxc4! dxc4 29 Be3! Qd1+ 30 Kf2 Qxa4 31 Bxg5! Qe8! 32 Qe6+ Qf7 33 Qxe7 Qxf3+ with a draw by perpetual check. Although securing the passed e-pawn looks strong, the weakening of the a8-h1 diagonal turns out to be problematic. Safer was 26 Re1. Allowing the d-pawn to advance with a gain of tempo. Instead 27 Nc5 Bxc5 28 bxc5 d4 29 Rf2 or 27 Nb2 Qb6+ 28 Kh1 d4+ 29 Bg2 give more time to defend. White's only hope is a desperate counter attack, since the d-pawn cannot be held: 30 Bg2 Be4! 31 Bxe4 fxe4 32 Qxe4 d3 33 Nc3 d2 etc. Judging the piece-down ending as lost after 32 Qxb6 axb6 33 Nc3 d2 34 Bxd2 Nxd2. More testing was 33 e6! threatening mate, but after 33...Rd6! 34 Qxh7 Kd8! 35 Qh8+ Kc7 36 Qxg7 dxe2! the pawn queens, while here 36 Qh5 d2! is similar to the game. White resigns, as there is no perpetual check, and stopping mate on h1 will cost too much material.
 * 1.d4 Nf6**
 * 2.c4 e6**
 * 3.Nf3 b6**
 * 4.g3 Ba6**
 * 5.b3 Bb4+**
 * 6.Bd2 Be7**
 * 7.Nc3 0-0**
 * 8.Bg2 c6**
 * 9.e4 d5**
 * 10.exd5 cxd5**
 * 11.Ne5 Bb7**
 * 12.0-0 Nc6**
 * 13.Bf4 Na5**
 * 14.Rc1 Ba3**
 * 15.Rb1 Bb4**
 * 16.Na4 Ne4**
 * 17.a3 Be7**
 * 18.cxd5 ---**
 * 18.--- exd5**
 * 19.b4 Nc6**
 * 20.Rc1 Rc8**
 * 21.Bh3 f5!**
 * 22.f3 Nd6**
 * 23.Qd3 Nxe5!**
 * 24.dxe5 Rxc1**
 * 25.Bxc1 ---**
 * 25.--- Nc4**
 * 26.f4?! ---**
 * 26.--- b5**
 * 27.Nc3?! ---**
 * 27.--- Qb6+**
 * 28.Rf2 d4**
 * 29.Ne2 Rd8**
 * 30.Qxf5!? ---**
 * 30.--- d3**
 * 31.Qe6+ Kf8**
 * 32.Qf5+ ---**
 * 32.--- Ke8**
 * 33.Qxh7 ---**
 * 33.--- d2!**
 * 34.Bxd2 Rxd2**
 * 35.e6 Rd1+**
 * 36.Bf1 Qxe6**
 * 37.Qh5+ Kf8**
 * 38.Nc3 Qc6!**


 * 0-1**


 * Solution:** 1 ... Bg2+! 2 Rxg2 (2 Kxg2 Qh3+ 3 Kf2 Qf3# or 3 Kh1 Qxh2#) 2... Re1+ 3 Qf1 Rxf1+ 4 Rg1 Qxh2#.