They say, that a loss is a small death. And any mistake in an important game often leaves a big wound. So that it does not heal for a long time. In the 8th round the massive fight between Russia and Ukraine took place. In the men's section the match was decided in a game of two...Ukrainian grandmasters. The thing is that one of them became Russian a few years ago.

Karjakin,Sergey (2785) - Volokitin,Andrei (2709)
Russia - Ukraine

After the unsuccessful opening Andrei was defending quite well and almost managed to escape. But the belief in chess aphorisms played a trick. One of them (Tarrasch is the author) says that rook endgames are never won. Apparently, there are exceptions.
43...Nxe7?
Too early. The good way to bring the doctrine of Tarrasch into life was in 43...Rb7! 44.b5+ (or 44.Kf5 Nxe7+ 45.Ke6 Ng6 46.Rxb7 Kxb7 47.h5 Nf4+ with equality) 44...Rxb5 45.h5 (also not dangerous 45.Bf8 Rb2 46.h5 Re2+ 47.Kd3 Rf2=) 45...Nxe7 46.Rxe7 Rxh5 47.Re6+ Kd7 48.Rxf6 Ke7 - this rook endgame is indeed drawn.
44.Rxe7 Rxb4+ 45.Kf5 Rxh4
Now, due to white king breaking to the pawn f6 and the fact that black king is cut off, White succeeds.
Sergey conducted the stage of converting his advantage as a computer:
46.Re4!
The only winning move.
46...Rh8 47.Rd4 Kc5 48.Rd3

48...Ra8
Perhaps more practical chances were left after 48...Rh3, after what White could win by 49.Kxf6 Kc4 50.Ra3! (only like this) 50...Kb4 (or 50...Kd5 51.Ra5+ Kd6 52.f4) 51.Re3 Kc4 52.Kf5 Kd4 53.Re4+ Kd5 54.Re5+! (the only) 54...Kd6 55.f4 Rh8 56.Kg6 Rf8 57.Re4 Kd5 58.Ra4 and so on.
49.f4 Ra4
Or 49...Rf8 50.Rd7 Kc6 51.Ke6 f5 52.Rg7 Kc5 53.Rf7+-
50.Rd7 Kc6 51.Rf7 Kd6 52.Rxf6+ Ke7 53.Kg6!
With the black rook on "h" line there was a saving move to h6, but now there is not.
53...Ra1 54.Rf7+ Ke8 55.f5 Rg1+ 56.Kf6 Rf1 57.Ra7 Rf2 58.Ra8+ Kd7 59.Rf8 Rh2 60.Kg7 Rg2+ 61.Kf7 Ra2 62.f6 Ra7 63.Re8 Ra6 64.Re1 1–0

One cannot but mention the emotional fight of the leaders.

Kramnik,Vladimir (2797) - Ivanchuk,Vassily (2769)
Russia - Ukraine

49...Rc2
After the game very disappointed Vassily showed Vladimir quasi winning variation 49...Kg6 50.g3 Ra1+ 51.Kg2 Re1 52.Kf2 Ng4+? 53.hxg4 h3, on which Russian showed the resource 54.Nf4+! , which leaded to the win for White - 54...gxf4 55.Kxe1 fxg3 56.Rh5 and so on.
Nevertheless Ukrainian grandmaster was then sadly sitting at the table for a long time, apparently thinking that he missed a win somewhere.
Waiting move 49...Rb2 would pay off in case of 50.g3? g4!.
But in fact after 49...Rb2 an easy draw could be reached by 50.Nc3, because in the variation 50...Rb3 51.Nxe4 Rxe3? 52.Nxf6 Rxe5 53.Ng4+ Black loses a piece.
50.g3! hxg3
No chances are left after 50...Ng4 51.hxg4 h3 52.Rb5 (52.Rxe4 Rxe2!) 52...h2 53.Kg2 Rxe2+ 54.Kh1 Rxe3 55.Kxh2 with a solid position for White.
51.Nxg3 Rh2 52.Nxe4 Nxe4 53.Rxe4 Rxh3 54.Kg2 Rh4 55.Re8
This unbreakable endgame Ivanchuk played for a long time, but could not do anything – draw..

This is how Russians kept the winning score and broke away from the rivals. Now everything is in their hands. I think nothing can prevent them from winning, at last, the gold medals, because they've already passed the main rivals.

In the match Azerbaijan – China the surprisingly quick loss of Mamedov was compensated by the bright win of one of the main scorers for the Caucasus team.

Mamedyarov,Shakhriyar (2729) - Wang,Yue (2703)
Azerbaijan - China

White pawns are quickly running to the 8th rank with the support of the bishops. It is possible to hold them only with a very accurate, study-like game.
25...Rc4?
Not a right path. He should have taken an important pawn on the way: 25...Rc2! 26.a5 Rxe2! 27.a6 Re1+ 28.Kg2 Ra1, and after 29.b4 he has a counter play - 29...d3! 30.b5 Ne4 31.Be5 (very easy is 31.b6 Nc5 32.Be3 d2! 33.Bxd2 Nxa6 with equality) 31...Ra5 32.Bc7 Ra1 33.Bxe4 fxe4 34.b6 d2 35.b7 h5 36.b8Q+ Kh7 37.Be5 d1Q 38.Bxa1 Qf3+ 39.Kh3 Qg4+ 40.Kg2 Qf3+ 41.Kg1 Qd1+ with perpetual check.
It is interesting if there is anyone on Earth who can calculate all this at the board?
26.a5 Ne4 27.a6 Ra4 28.b4! Nc3 29.Bc7!
The idea of overlay on a5 was probably missed by the Chinese player.
29...Nxe2+ 30.Kg2 Nc3 31.Ba5 Nb5 32.Bc6 Rxa5 33.Bxb5!
Apparently, was also winning 33.bxa5 Na7 34.Bd5 Kf8 35.Kf3 Ke7 36.Ke2.
33...Ra1 34.Bc4 d3
The main line was calculated beforehand: 34...Kf8 35.b5 Ke7 36.b6 Kd6 37.a7 Kc6 38.Bd5+! with an extra piece for White at the end.
35.Bxd3 Kf8 36.b5 Ke7 37.b6 Kd6

Now white bishop is not in time to get to diagonal h1–a8, but, with black passed pawn being absent, there is time for distracting maneuver
38.Bb5! Kc5 39.b7 White pawns pass.. 1–0

In the match Germany – Hungary one of the most solid and stable grandmasters of the last decades suddenly collapsed.

Naiditsch,Arkadij (2712) - Leko,Peter (2737)
Germany - Hungary

27...gxh5?
Strange move, which is difficult to predict from a solid fighter. After obvious 27...N7f6 the whole game would be ahead.
28.Ng3 Kh8?
Much more stubborn 28...Kg8 29.Nf5 (29.Nxh5 Kh8!) 29...Qf8.
29.Nf5! Qf6 30.Nd6
That's it! Just in a few moves the solid position of Black became a bunch of ruins.
30...Rg8 [30...Qxg5? 31.Nxf7+] 31.Ndxf7+ Kg7 32.Rxe6 Qf4 33.Qxf4 Nxf4 34.Re7 1–0

As expected (for instance, by me) the girls from Poland, tired after the fight with Russians, did not cope with the pressure from the top team and capitulated.

Socko,Monika (2467) - Hou,Yifan (2599)
Poland - China

The world champion is not only playing strong, but also paralyzes her opponents with her authority. They often do not believe that they can escape with a normal logical play, and start strange escapades.
31.Qc7?
After normal move 31.Qb2 White kept a good compensation for the pawn. I think that Black almost did not have chances for a win in this case.
31...Rd7!
Now White's things are bad. In the end Hou was ruthless as a machine.
32.Qb8
Instantly lost 32.Qxb6 Rd2!.
32...Rd1!
Fruitless is 32...Rd2 due to 33.Qf4.
33.Ra8 Nd7!
This move was made in one second – specially for the time trouble of the opponent.
34.Qh8+ Kh6 35.Ra1
She is not going to get the Black king: 35.Rg8 Qxh3! 36.Qg7+ Kg5–+
35...Rd2
Separated white forces can't withstand Black's attack.
36.f4 exf3 37.Ra4 g5! 38.Rc4 Rd1 39.Rc6+ f6 40.Kf2

40...Rxf1+! Final strike. Mate is inevitable. 0–1

Zhao,Xue (2549) - Rajlich,Iweta (2412)
Poland - China

Many can patiently defend. But few can do it forever...
55...g5
Not yet a mistake.
56.f5 h5?
And this nervous escapade leads to a loss...through a draw!
She'd better calmly maneuvered with 56...Ke5.
57.Ne3+?
Chinese are not made of iron, too. She could win without special delights: 57.gxh5! Ke5 (57...Bb2 58.Ne3+ Kc6 59.h6) 58.h6 Kxf5 59.Kc2! Kg6 60.Kxc1 Kxh6 61.Kd2 Kh5 62.Ke3 g4 63.h4+-
57...Bxe3?
Surprising decision, isn't it?
I have only one version. Iveta could think that in the variation 57...Ke5 58.gxh5 Bxe3 59.h6 White pawn passes. The thing is that... I also thought the same, tired commentator, at the end of the report. But in fact Black could hold it with 59...Bd4! 60.h7? Kd5!.
58.Kxe3 hxg4 59.hxg4
There are no doubts about this endgame.
59...Ke5 60.Kf3 Kd5 61.Ke2 Kd6 62.Kd2
White reaches the pawn on g5. 1–0

Iconic women match Russian – Ukraine was marked with the twists of the plot and incredible mistakes. And if Ushenina won against Pogonina without serious mistakes, the other games were far more complex.

Kosintseva,Nadezhda (2524) - Zhukova,Natalia (2442)
Russia - Ukraine

40...Nf6?
If Natalia would get this position as a tactical study, she would certainly find simple 40...Ngf4+! 41.gxf4 Nxf4+ 42.Kh2 Rxg1! With the decisive advantage for White - 43.Rb2 (43.Kxg1 Nh3+; 43.Qxg1 Qxc2+) 43...Qxc3 44.Rc2 Qd3 45.Rd2 Rf1!.
But the things is that this was the last move in a time-trouble before the time-control and probably nobody gave a hint that there was tactics in this position:)
41.Ne3 Nf8
A beautiful draw happens after 41...Nh5 42.Ne2 Nhf4+ 43.gxf4 exf4 44.Nd4 fxe3 45.Nxb3 Nf4+ 46.Kg3 Nh5+ 47.Kg2 Nf4+ and so on.
42.Qe2 Qb1 43.Qf1 Qxf1+ 44.Nxf1
White managed to balance the game. In the further game the Ukrainian was just unrecognizable. She played too passively and unconfidently.
44...N8d7 45.Ne3 Nb6 46.c4 bxc4 47.Nxc4 Nxc4 48.Rxc4 Ne8 49.Ne2 Kf8 50.Kf2 Ke7 51.Ke3 Kd7 52.Rc1 Rxc1 53.Nxc1 Nf6 54.Ne2 Kc8 55.g4 g5? 56.h5! Ng8 57.Kd3 Kb7 58.Kc4 Kb6 59.Nc3 Ne7 60.Nd1 Ka6 61.Ne3 Kb6 62.Kb3 Kb5 63.Nc4 Nc8 64.Na3+ Kb6 65.Ka4 Ka6 66.b5+ Kb7 67.Kb4 Nb6? [67...Kb6 68.Nc4+ Ka7=] 68.Nc2 Nc8 69.Ne3 Ne7 70.Nc4 Kb8

71.b6! The decisive break. 71...Nc8 72.Kb5 Ne7
Or 72...cxb6 73.Ne3 Ne7 74.Kxb6 Kc8 75.Nf5 with the win for White.
73.Na5 cxb6 74.Nc6+ Nxc6 75.Kxc6 b5! 76.Kxd6!
Of course not 76.Kxb5 Kb7=
76...b4 77.Ke7
The rest is too simple.
77...b3 78.d6 b2 79.d7 b1Q 80.d8Q+ Kb7 81.Qd7+ Kb8 82.Qd6+ Kc8 83.Qxh6 Qb7+ 84.Kf8 Qb3 85.Qf6 1–0

Kosintseva,Tatiana (2530) - Lahno,Kateryna (2542)
Russia - Ukraine

In the previous play Tatiana missed a lot of possibilities to win, but she has one left, and quite an obvious one.
112.Rh7?
Incredible mistake, one in one the crucial blunder of Gelfand in the tragic tie-break game in the title match with Anand. There Boris quite the same protected the pawn on h6 with the rook from h7 and missed a win.
Easy 112.h7 Rh6+ 113.Bh4 Bd3 (113...Kb8 114.Rg7) 114.Ra8+ Kb7 115.h8Q leaded to the goal.
112...Kxd8! 113.b7 Rxh6+! 114.Rxh6 Kc7 115.Rh7+ Kb8 116.Kg3 Ba6 117.Kf4 Bxb7
Eternally sad Russian played this balanced endgame for 40 moves until the captain of Russian women's team Sergey Rublevsky stopped her. A draw!

So the Slav derby ended in a draw and the Chinese jumped to the first place. And they have already met with all the rivals... It is difficult to imagine who and how can stop them now.