Blunder (10)

In the diagram position (Cheparinov - Lopez-Martinez, Rijeka 2010) White's last move 21.Qf4-f3?? was terrible.

Now 21.- Bxc2+! destroyed White's position. Cheparinov could have played 22.Kc1 now, but I guess that the loss of the pawn c2 is unforgiveable in this french line. So he played 22.Kxc2 and gave Black the opportunity to demonstrate the small combination: 22.- Qb3+ 23.Kc1 Nb4! Now it's obvious why Qf3 was bad. The knight on b4 cannot be taken because the queen is unprotected. 0-1

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