Don't blame the Slav, which does just fine again. The novelty is 18.a5 (prepared?) and Anand plays slightly inaccurately almost immediately. 18...Bb4, Rybka's choice, is likely right as it better frees Black's position and temporarily ties the Rook to the a-file. If 19.Ra4, then the Bishop can be played to e7, but now with the Rook misplaced. In short, the Slav is holding up beautifully. Will Anand abandon it in game 10?