<69...Rd2?? A harsh assessment, because the game was drawn before this move and remains drawn after it. But the difference is that after 69...Kd8, it's trivial, and now, it's anything but. I'm not sure what the right drawing procedure is after Tregubov's next move, and clearly Akobian wasn't either, as he managed to lose it. So practically speaking, it's a blunder. The obvious question then is why he did it. The answer is that it's an attempt to improve on the variation I gave instead. Black wants to bring his king over, but without allowing White to do the same. It's a very sophisticated idea, but it meets a simple tactical refutation. [69...Kd8 70.Kd6 Ra6+ 71.Rc6 Ra1 produces a position I'd expect a good club player to hold, and for Akobian to defend in his sleep, with the flu.]

70.Rc5! Now ...Kd7/...Kd8 is impossible, as 71.Rd5+ wins immediately. Now the problem for Black is that his king is cut off, and while it's still a draw Black will have to do some thinking: auto-pilot is off.

70...Ke7 [There was still one relatively simple draw, again based on bringing the king over as fast as possible: 70...Re2+ 71.Kd6 Kd8 72.Rh5 Kc8! (72...Rd2+ 73.Kc6) 73.c4 Rc2 74.c5 Kb7 with the Karstedt draw.]

71.Rd5 Now Black has to show some finesse, and that's not at all easy if Akobian is just playing on the increments.

<69...Rd2. Simpler is 69...Kd8!, of course.

70.Rc5 Ke7 71.Rd5 Rh2 72.Kd4. White achieved a lot – he cut the Black's king on the d-file and prepared his own king's march to c5, but this is not enough to claim a victory.

72...Ke6? A big mistake! The simplest way to hold the balance is 72...Rc2! with the idea 73.c4 Rd2+ 74.Kc5 Rxd5+! 75.Kxd5 Kd7, and Black has the opposition – draw.

73.Kc5! Now White wins.

73...Rh8 74.Rd6+! The only move. 74.c4? allows Black to escape by 74...Rc8+ 75.Kb5 Rb8+ 76.Ka6 Rc8 77.Rd4 Ke5!

74...Ke7 75.c4 Rc8+ 76.Rc6 Rb8 77.Rc7+ Kd8. Black's attempt to achieve elementary Philidor positions fails, because his rook is passive.

78.Rh7 Rb1 79.Kc6! And Black's king cannot get to the shorter side of the board.

79...Rg1 80.Rh8+ Ke7 81.c5 Rc1.

82.Rb8. As you can see, Pavel also was nearing collapse at this point. Much more convincing is 82.Rc8!

82...Rc2 83.Rb5 Kd8 84.Rb8+ Ke7 85.Rb1 Kd8 86.Rh1 Ke7. Akobian should have tested his opponent by 86...Rc3, after which White must find the maneuver 87.Rh8+ Ke7 88.Rc8!

87.Rd1. The rest is very easy.

A very instructive article by GM Valeriy Aveskulov <How the Grandmasters played Rook endgames in 2009…> anotates this rook endgame and can be found here: http://lessons.chessdom.com/three-r...