Oll, Lembit – Tkachiev, Vladislav

2645 1997 · Draw

1997, Modern Defense: Oll (2645) faces Tkachiev (2615) in a quiet fianchetto structure where White builds up and plays d4. Then the game swings twice in two moves. On move 20, 20.Bf3 lets a chance slip — the evaluation moves from −0.1 to +4.6 for White. Black immediately returns the favour with 21...Bg2, and the position falls back from −5.0 to −0.3. After those mirrored misses, the queens come off on move 31 and the rook-and-bishop endgame fades out by repetition. Accuracy: 74% for White, 85% for Black. The takeaway: in calm-looking positions the tactical window opens and shuts within a single move — and even players at this level can miss it back to back.