Two games from the Olympiad

[FEN "6k1/3n2pp/4p3/5p2/rpNP4/1Nn1P1P1/2R2PKP/8 w - - 0 24"]
24. Nc1 b3 {Nice play, Black has this all worked out. the b-pawn beats a Rook and Knight.} 25. Rxc3 Rxc4 26. Rxc4 {Missing a black move to come. White had to play Ne2 , then Black has Rb4.} 26... b2 27. Rc8+ Kf7 28. Rc7 {Now b1=Q Rxd7+ and Rc7. The Rook and Knight can hold back the Queen. But...} 28... Ke8 {The move White missed when not playing Ne2. 0-1}

[FEN "r3k3/1p2qp2/2p1p2p/p4prP/P2P1b2/2P2B2/1P2QPP1/R4R1K w q - 0 25"]
25. Rfe1 {Missing Black's threat. White had to play Kg1.} 25... Rxh5+ {Bxh5 then Qh4+ and mate.} 26. Kg1 {Now it is the standard Rooks sac, Queen check and mate trick.} 26... Rh1+ 27. Kxh1 Qh4+ 28. Kg1 Qh2+ 29. Kf1 Qh1