ODT130205

=**Cheng wins Australian Open Championship**=




 * Problem:** White to play and mate.

FM Bobby Cheng of Melbourne won the 2013 Australian Open Championship in Sydney last month at the age of only 15. This was not Cheng's first headline-grabbing result, as he won the world under 12 championship in 2010 not long after emigrating from New Zealand to Australia.

Cheng dominated the strong field of 112 players in the open section, headed by top-100 GM Igor Khenkin, Germany's player of 2012. After starting with a half-point bye, Cheng won his next four games followed by a draw in round 6 with Australia's number one player, GM Zong-Yuan Zhao. Then followed another four game winning streak, establishing a point lead going into the final round. Cheng accepted the draw offer from his closest rival, Queensland IM Moulthun Ly, to finish first on 9½/11, a point clear of Ly, Zhao and IM Max Illingworth, who tied for second place.

Today's game is Cheng's win over Khenkin in the eighth round to take the sole lead. Cheng is playing with the white pieces. media type="custom" key="25162848" White has chosen a relatively quiet variation against the Slav Defence. Black steers the game into a Stonewall Dutch configuration with a view to attacking on the kingside. White threatened to lock up e5 with f2-f4, slowing Black's kingside intentions. But this move also has the drawback of weakening the pawn on d5. White re-routes the bishop to b3 to attack d5 and Black immediately jumps onto the vacant a6-f1 diagonal with his own light-squared bishop – often left out of play in the Stonewall. Gaining a tempo by the threat of 19 Bxd5 forcing Black's reply, whereas after 18 Nd3 Bc4! Black would have solved his d5 problems. Staying with the d5 strategy, White is prepared to exchange his dark-squared bishop on c3. Instead 20 Bxd6 Nxd6 21 Re1 Bc4! covering d5. A double-edged move – Black sees the opportunity to play aggressively against White's king using his rook along the third rank, but also opens the e-file for White's rook and gives the e5 outpost to his knight. 22... Bc4 was equal as 23 Bxc4 Rxc4 24 Ng5 Qd7 defends d5 indirectly. White threatened 25 Ne5 winning the exchange, but this move fails tactically. The immediate exchange sacrifice 24.... Rxf3!? 25 gxf3 also looks inadequate after either 25... Nh5 26 Qc1 Bc4 27 Bxc4 dxc4 28 Re5 or 25...Bc4 26 Bxc4 Qg6+ 27 Kh1 dxc4 28 Qc2. White wins the exchange for a pawn and liquidates to an ending after this, but the exchange sacrifice 25... Rxf3!? is somewhat neutralised by 26 Bd1 Ng4 27 Bxf3 Qxh2+ 28 Kf1 as the king can escape. Though after 28... Bb7 (threatening 29...Qxf4) White still has to surmount serious practical problems. White's advantage is not large, but it is impressive how 15 year old Cheng goes about winning the ending. Firstly he activates his rook down the e-file. The f5 pawn is hard to defend, so the black rook goes after White's a-pawn. In the run up to the time control, White misses an instant win by 36 Re3! Bb5 37 Ne5+ Kh6 38 Rh3+ Nh5 39 f3! winning a piece by 40 g4. After the text, threatening 37 Ne5+, Black could have resisted better by 36... Kh6. Instead he loses the f5 pawn and his king is subjected to a mating attack.
 * 1.d4 d5**
 * 2.c4 c6**
 * 3.Nf3 e6**
 * 4.e3 Nf6**
 * 5.b3 Bb4+**
 * 6.Nbd2 Ne4**
 * 7.Bd3 f5**
 * 8.0-0 Nd7**
 * 9.Bb2 0-0**
 * 10.a3 Bd6**
 * 11.b4 Qf6**
 * 12.Ne1 e5!?**
 * 13.cxd5 cxd5**
 * 14.Ndf3 exd4**
 * 15.Bxd4 Qf7**
 * 16.Bc2! b6!**
 * 17.Bb3 Ba6**
 * 18.Be5! ---**
 * 18.--- Ndf6**
 * 19.Nd3 Rac8**
 * 20.Re1! ---**
 * 20.--- Nc3**
 * 21.Bxc3 Rxc3**
 * 22.Nf4 Bxf4?!**
 * 23.exf4 Rd3**
 * 24.Qb1 Qh5**
 * 25.b5! Bxb5**
 * 26.Bd1 Bc4**
 * 27.Ne5 Rxd1**
 * 28.Qxd1 Qxd1**
 * 29.Raxd1 Rc8**
 * 30.Nf3 Rc7**
 * 31.Re6 Kf7**
 * 32.Ng5+ Kg6**
 * 33.Re5! Rc5**
 * 34.Nf3 Ra5**
 * 35.Ra1 Bd3?**
 * 36.Re7? ---**
 * 36.--- Bb5?**
 * 37.Nh4+ Kh5**
 * 38.Nxf5 g6**
 * 39.Nd4 Bd3**
 * 40.h3 Ra4**
 * 41.Ne6 Re4**
 * 42.Rd1 Bc4**
 * 43.g4+ Kh4**
 * 44.Kg2 h5**
 * 45.Nd4! hxg4**
 * 46.hxg4 Rxe7**
 * 47.f3 Nxg4**
 * 48.Rh1+ Resigns**


 * 1-0**


 * Solution:** 1 Nf8! g6 (1... Rxf8 Qxf8#; 1... Bg6 2 Nxg6+ hxg6 3 Qh3#) 2 Qf6+ Rg7 3 Ne6 and Black can only delay Qxg7# by sacrificing all her pieces.