Coming into round 5 seven players led the FIDE Grand Prix in Thessaloniki, and only one - Rustam Kasimdzhanov had White. Normally we'd think this would give him a leg up, but instead he was the day's only loser. His opponent, Leinier Dominguez, has now won three in a row and enjoys the sole lead with 3.5 points. Dominguez played the solid Bogo-Indian, in shocking violation of the guild's policy of playing the Gruenfeld whenever possible, and was rewarded for his insouciance. Kasimdzhanov misassessed the rook ending he started to head for with the exchanging combination starting with 22.Qxe4 and directly permitted with 26.Rc5. The resulting ending wasn't lost but it was very difficult, and some neat moves like 28...Kf8, 33...Re2 and 39...Ke8 helped push White over the edge.
The other five games went in every direction. Ivanchuk-Kamsky was drawn in just 25 moves and in half an hour, but the other draws all made it to at least the second time control. Svidler-Topalov saw White gain an advantage after 23...Nf8, but the position re-equalized after the natural 26.Ne5. (26.Nd2 was better, even though it doesn't force Black to initiate the swap.) Ponomariov-Grischuk was a Berlin that always looked pretty comfortable for Black. Interestingly, Grischuk wasn't completely sure that the final position was drawn, so the endgame mavens among you may wish to delve and see.
Two games made it past move 80, both Gruenfelds. Bacrot-Morozevich saw Moro down the exchange in return for a pawn and a beautiful knight. Soon he was even a little better, and refused a draw by repetition. Soon he regretted it, and after inaccuracies on moves 60 and 61 and an outright error on move 64 (he needed to try 64...Nxb5) he was lost. The key moment came on move 66, when Bacrot had to decide which way to move the king: to the kingside, to deal with Black's most dangerous pawns, or to the queenside, to support his own passer and free his rook to deal with the pawns. He chose wrongly, keeping the king on the kingside with 66.Rb8 followed by 67.Ke4-f3. Instead, 66.Kd4 followed by 67.Kc5 probably won.
Nakamura-Caruana initially followed a somewhat similar trajectory: Nakamura's inaccuracies just before and after the time control turned an equal position into one that favored Black and may have been winning. Nakamura had some compensation for a couple of pawns, but had Caruana immediately started the plan he initiated a move later it might not have been enough. Instead of 45...c5, it would have been better to consolidate with 45...Kf7 and 46...Bc8 (or vice-versa). As things went, Nakamura got one of his pawns back, and while Caruana tried for a long time to win the resulting same-colored bishop ending he was unable to break through against Nakamura's accurate defense.
Round 6 Pairings: