Round four of the Grenke Chess Classic was an exciting one, featuring two games that were settled by blunders. In both games the player with Black won and the player trying to conduct a kingside attack lost.
Since he is leading the tournament and defeated Magnus Carlsen in round 3, we'll give Arkadij Naiditsch his due and start with his game. Playing his countryman David Baramidze, he came up with a very provocative way of meeting the English. The position was practically begging for Baramidze to attack, and he took up the challenge with gusto. First he sacrificed a pawn, then the exchange and a pawn - which he turned into a full rook sacrifice, and then another piece. The last one was one sac too many, and just five moves later Baramidze realized the attack was out of gas, and resigned. Without the last sacrifice, the game would have remained unclear and anything would have been possible.
Carlsen had trouble with the black pieces against Viswanathan Anand in their world championship match last year, and today he switched openings again, opting for a Stonewall Dutch. After 19...e5 the board quickly opened up, and Carlsen's brave - and correct - 25...Bb2 raised the stakes. White's attack had better break through, or Black's a-pawn would soon promote. Play continued logically through Black's 31st move, but on move 32 Anand made an amazing blunder, 32.Rd7?? It wasn't difficult to refute, and the oddness was compounded by the fact that Anand only spent 52 seconds on the move. Anand wasn't speaking afterwards, so it's unclear if he overlooked something that happened in the game or if he hadn't found the right move (32.Re6). Anyone can overlook something, but the speed with which he executed the blunder was remarkable, especially given that he wasn't in time trouble.
The other games were drawn. Fabiano Caruana had chances for more against Michael Adams, with the last opportunity coming on move 32. After Caruana played 32.Bc4 rather than 32.Kf3, Adams was able to limp home with a draw. The opening between Etienne Bacrot and Levon Aronian was unusual and interesting before it resolved into a very equal QGD-like structure.
The games (with my notes) are here, and these are the pairings for tomorrow's round 5 (of 7):