[Title "White to move"]
[FEN "1r3rk1/1p4bp/p2p1q2/2pPn1p1/B1PnRp2/PPN2P1P/2QB2P1/3R2K1 w - - 5 27"]
This is a diagram from the game between Del Rey, Diego and Efimenko, Zahar on the Zalakaros Chess Festival after 26...Nd4. White answered with 27.Rxd4. I don't understand why white needed to sacrifice his rook for the knight in this position.