Steven played in the ongoing 5th Singapore Master Open Championship 2008. So far he had produced two upset by beating higher rated player - Chinese GM Zhao Jun (FIDE 2568) and Vietnamase GM Bui Vinh (FIDE 2507) .
Below is his round 1 upset against Chinese GM Zhao Jun.
Yap,Kim Steven (2386) - GM Zhao,Jun (2568) [A00]
5th Singapore Masters Teck Ghee Community Club (1.1), 10.12.2008
1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 Qb6 5.Nb3 Nf6 6.Nc3 e6 7.Bd3 a6 8.0–0 d6 9.Kh1 Qc7 10.f4 Be7 11.Be3 b5 12.a3 Bb7 13.Qf3 0–0 14.Qh3 b4 15.axb4 Nxb4 16.Na5 Nxd3 17.cxd3 Rab8 18.Rfc1 Qd7 19.Bd4 Ba8 20.Nc4 d5 21.Nb6 Qd8 22.Nxa8 dxe4 23.Bxf6 Bxf6 24.dxe4 Rxa8 25.e5 Be7 26.f5 Qb6 27.f6 gxf6 28.Qh4 Rfc8 29.exf6 Bf8 30.Ra4 Kh8 31.Rg4 Rc5 32.Rg1 Rf5 33.Ne4 Qe3 34.Ng5
34...Qxg1+ Force move. 35.Kxg1 Bc5+ 36.Rd4 Bxd4+ 37.Qxd4 Rxg5
A topical endgame position has arise. A queen versus two rooks with black has extra pawn which doesn't add any advantage for black because it's difficult to mobilize. Fritz 11 evaluate this position as equal.
38.h4 Rd5 39.Qf4 Rg8 40.Qc7 Rf8 41.Qe7 Kg8??
The main mistake. Black should sit tied with 41...Rdd8 and white can't made any serious progress. 42.Qa3! White is threatening Qg3+ followed by Qg7++ checkmate on g7! 42... Rfd8 43.Qg3+ Kf8 44.Qg7+ Ke8 45.Qg8+ Kd7 46.Qxf7+ Kc6 47.Qxe6+ R5d6 48.Qe4+ Kb6 49.f7 Rf6?? Black is already lost but he made white job easier by separting black "twin brothers" - the rook on d8 and d6. Both should not separate from each other because after 50.Qb4+ the f6 rook will be captured 50...Kc6 (50...Kc7 51.Qe7+ Rd7 52.Qxf6) 51.Qc3+ Kd7 52.Qxf6 1–0
In round 3 he produced another upset by beating Vietname GM Bui Vinh.
Yap,Kim Steven (2386) - GM Bui,Vinh (2507) [A00]
5th Singapore Masters Teck Ghee Community Club (3.1), 11.12.2008
1.e4 c5 2.Nf3 e6 3.c3 d5 4.exd5 Qxd5 5.d4 Nf6 6.Be2 cxd4 7.cxd4 Nc6 8.Nc3 Qd6 9.0–0 Be7 10.Bg5 0–0 11.Bb5 Nb4 12.Qb3 Nbd5 13.Bc4 Nxc3 14.bxc3 b6 15.Rfe1 Bb7 16.Ne5 Rac8 17.Re3 Bd5 18.Bxd5 Nxd5 19.Bxe7 Qxe7 20.Rf3 Qg5 21.g3 Nf6 22.h4 Qh5 23.Re1 Ng4 24.Rf4 Nxe5 25.Rxe5 Qg6 26.c4 Rfd8 27.a4 Rc7 28.Rg5 Qh6 29.a5 Rdc8 30.axb6 axb6 31.Qxb6 Rxc4 32.Rc5 R4xc5 33.dxc5 e5 34.Qb7 Rf8 35.Rc4 Qd2 36.Qe4 Re8 37.c6 Qd1+ 38.Kh2 f5? 39.Qxf5 Rf8?? Black probably missed white's next move 40.Qxf8+! Kxf8 41.c7 and nothing can stop white c pawn from promoting. 1–0