[Event "corr."] [Site "masterchessopen.com Germany"] [Round "0"] [White "Mertens Klaus (GER)"] [Black "Koch Hans Georg"] [Result "1-0"] [WhiteElo "2064"] [ECO "C70"] [Opening "Spanish: 4.Ba4"] 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Nxe4 6.d4 b5 7.Bb3 d5 8.dxe5 Be6 9.Qe2 Be7 10.Rd1 Nc5 11.c4 d4 12.cxb5 d3 13.Qf1 Nd4 14.Nxd4 Qxd4 15.Bxe6 fxe6 16.Nc3 O-O 17.Qe1 Rf5 18.Qe3 Qxe3 19.Bxe3 axb5 20.Nxb5 Rb8 21.Nd4 {#r} 1-0