Player profile
Mertens, Klaus
Dossier
24 of 25 games analyzed.
Accuracy: 90.5%
Opened Nf3: 5/5
Castled kingside: 12Same-side castling: 11Did not castle: 2Castled queenside: 1Opposite-side castling: 1
Fianchettoed kingside: 9Fianchettoed queenside: 7Played in the center: 6Played on the queenside: 4Played on the kingside: 3
Kept the bishop pair: 12Backward pawn: 12Initiated exchanges: 7Space advantage: 6Missed tactics: 5Isolated pawn: 5Active pieces: 5Avoided exchanges: 4Sacrificed material: 4Accepted short draws: 2
Openings
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As White 5 games 2W 3D 0L
King's Indian Attack 3 games 1W 2D 0L
(unspecified) 2 games 1W 1D 0L
(unspecified)
2 games
1W
1D
0L
Symmetrical Defense 1 game 0W 1D 0L
(unspecified)
1 game
0W
1D
0L
King's Indian Defense 1 game 0W 1D 0L
Fianchetto Variation 1 game 0W 1D 0L
(unspecified)
1 game
0W
1D
0L
English Opening 1 game 1W 0D 0L
Agincourt Defense 1 game 1W 0D 0L
Catalan Defense, Semi-Slav Defense
1 game
1W
0D
0L
As Black 11 games 1W 7D 3L
Czech Defense 3 games 1W 2D 0L
(unspecified) 3 games 1W 2D 0L
(unspecified)
3 games
1W
2D
0L
Indian Defense 2 games 0W 2D 0L
Wade-Tartakower Defense 2 games 0W 2D 0L
(unspecified)
2 games
0W
2D
0L
English Opening 1 game 0W 1D 0L
Symmetrical Variation 1 game 0W 1D 0L
Four Knights Variation
1 game
0W
1D
0L
Catalan Opening 1 game 0W 1D 0L
(unspecified) 1 game 0W 1D 0L
(unspecified)
1 game
0W
1D
0L
Pseudo Queen's Indian Defense 1 game 0W 0D 1L
(unspecified) 1 game 0W 0D 1L
(unspecified)
1 game
0W
0D
1L
King's Indian Attack 1 game 0W 1D 0L
Symmetrical Defense 1 game 0W 1D 0L
(unspecified)
1 game
0W
1D
0L
King's Indian Attack, with Bf5 1 game 0W 0D 1L
(unspecified) 1 game 0W 0D 1L
(unspecified)
1 game
0W
0D
1L
Nimzo-Indian Defense 1 game 0W 0D 1L
Three Knights Variation 1 game 0W 0D 1L
(unspecified)
1 game
0W
0D
1L
Blunders Top 4 of 79
This player's costliest moves in analyzed games. Can you find the winning move?
Games Showing all 25 games
| Date | Event | Round | Color | Opponent | Result | Accuracy % | First moves |
|---|---|---|---|---|---|---|---|
| 2026.08.26 | Round 9: Mertens, Klaus - Stuemer, Paul | 9.12 | 2026.08.26 Stuemer, Paul (4635841) (2003) | ½ | 96.60% | 1. Nf3 Nf6 2. d4 g6 3. c4 Bg7 | |
| 2026.08.25 | Round 8: Mertens, Klaus - Schaefer, Bernd | 8.15 | 2026.08.25 Schaefer, Bernd (34601317) (1974) | ½ | 81.60% | 1. Nf3 Nf6 2. g3 d5 3. Bg2 Bf5 | |
| 2026.08.24 | Round 7: Kalepky, Helmut - Mertens, Klaus | 7.17 | 2026.08.24 Kalepky, Helmut (24606928) (1925) | ½ | 89.90% | 1. Nf3 Nf6 2. c4 c5 3. Nc3 Nc6 | |
| 2026.08.23 | Round 6: Mertens, Klaus - Tozaki, Halil | 6.20 | 2026.08.23 Tozaki, Halil (6302505) (1875) | 1 | 92.90% | 1. Nf3 Nf6 2. g3 d5 3. Bg2 g6 | |
| 2026.08.22 | Round 5: Kuhn, Andreas - Mertens, Klaus | 5.20 | 2026.08.22 Kuhn, Andreas (4608470) (1855) | ½ | 95.10% | 1. d4 Nf6 2. c4 e6 3. g3 Bb4+ | |
| 2026.08.21 | Round 4: Mertens, Klaus - Busic, Nedjeljko | 4.19 | 2026.08.21 Busic, Nedjeljko (24603457) (1866) | ½ | 93.40% | 1. Nf3 Nf6 2. g3 g6 3. Bg2 d6 | |
| 2026.08.20 | Round 3: Steingrobe, Udo - Mertens, Klaus | 3.13 | 2026.08.20 Steingrobe, Udo (12954039) (1968) | 0 | 78.80% | 1. d4 Nf6 2. Nf3 b6 3. Bg5 Bb7 | |
| 2026.08.19 | Round 2: Mertens, Klaus - Best, Ingeborg | 2.24 | 2026.08.19 Best, Ingeborg (16237056) (1817) | 1 | 97.40% | 1. Nf3 e6 2. g3 d5 3. Bg2 Nf6 | |
| 2026.08.18 | Round 1: Beuger, Ronald - Mertens, Klaus | 1.19 | 2026.08.18 Beuger, Ronald (24622982) (1821) | ½ | 87.20% | 1. Nf3 Nf6 2. g3 g6 3. Bg2 Bg7 | |
| 2025.09.25 | Round 5: Mueller, Lutz - Mertens, Klaus | 5.23 | 2025.09.25 Mueller, Lutz (4660579) (1908) | ½ | 92.80% | 1. d4 Nf6 2. Nf3 d6 3. Nc3 c6 | |
| 2025.09.23 | Round 3: Frick, Christoph - Mertens, Klaus | 3.23 | 2025.09.23 Frick, Christoph (4607090) (2094) | ½ | 90.70% | 1. d4 Nf6 2. Nf3 d6 3. Nc3 c6 | |
| 2025.09.21 | Round 1: Waldschlaeger, Juergen - Mertens, Klaus | 1.23 | 2025.09.21 Waldschlaeger, Juergen (4631145) (2109) | 0 | - | 1. Nf3 Nf6 2. g3 d5 3. Bg2 c6 | |
| 2024.07.13 | 9. offene Baden-W?rttembergische Senioren-Einzelmeisterschaft | 9.8 | 2024.07.13 Wengert, Ulrich | 1 | 92.90% | 1. e4 d6 2. d4 Nf6 3. Nc3 c6 | |
| 2024.04.14 | Round 9: Jahn, Constanze - Mertens, Klaus | 2024.04.14 Jahn, Constanze (4612450) (2042) | ½ | 87.90% | 1. e4 d6 2. d4 Nf6 3. Nc3 c6 | ||
| 2024.04.12 | Round 7: Luciani, Carlo - Mertens, Klaus | 2024.04.12 Luciani, Carlo (800627) (2159) | ½ | 91.50% | 1. e4 d6 2. d4 Nf6 3. Nc3 c6 | ||
| 2024.04.08 | Round 3: Schneider-Zinner, Harald - Mertens, Klaus | 2024.04.08 Schneider-Zinner, Harald (1604520) (2335) | 0 | 89.00% | 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 | ||
| 2023.09.13 | 20. RLP-Senioren-Open | 9 | 2023.09.13 Meyer, Armin (2197) | ½ | 92.90% | 1. Nf3 c5 2. g3 d5 3. d4 cxd4 | |
| 2023.09.12 | 20. RLP-Senioren-Open | 8 | 2023.09.12 Krueger, Erich (4624718) (2150) | 0 | 86.20% | 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 | |
| 2023.09.11 | 20. RLP-Senioren-Open | 7 | 2023.09.11 Stuemer, Paul (4635841) (2031) | ½ | 85.80% | 1. Nf3 Nf6 2. g3 g6 3. Bg2 Bg7 | |
| 2023.09.10 | 20. RLP-Senioren-Open | 6 | 2023.09.10 Haubt, Georg (4604016) (2082) | 1 | 89.20% | 1. Nf3 d5 2. d4 Nc6 3. g3 Bg4 | |
| 2023.09.09 | 20. RLP-Senioren-Open | 5 | 2023.09.09 Schwickert, Michael (1874) | 1 | 94.50% | 1. b3 Nf6 2. Bb2 e6 3. e3 Be7 | |
| 2023.09.08 | 20. RLP-Senioren-Open | 4 | 2023.09.08 Polster, Wolfgang (16231805) (2178) | ½ | 88.50% | 1. Nf3 g6 2. d4 Bg7 3. g3 c5 | |
| 2023.09.07 | 20. RLP-Senioren-Open | 3 | 2023.09.07 Wacker, Peter (4615751) (2260) | ½ | 90.10% | 1. e4 d6 2. d4 Nf6 3. Nc3 c6 | |
| 2023.09.06 | 20. RLP-Senioren-Open | 2 | 2023.09.06 Hesse, Rutger (16209419) (1900) | 1 | 96.10% | 1. Nf3 Nf6 2. d4 d5 3. g3 g6 | |
| 2023.09.05 | 20. RLP-Senioren-Open | 1 | 2023.09.05 Blosze, Winfried (24614300) (1799) | 1 | 90.80% | 1. e4 d6 2. Nc3 Nf6 3. Bc4 c6 |