Essentially the other games were fairly cautious affairs and even the most complicated of these, (Vachier_Lagrave-Gelfand) was agreed drawn in a double-edged endgame.
The Frenchman sacrificed the exchange for a couple of pawns to maintain the initiative, but the draw was agreed just as the pawn race was hotting up.
To be fair, Gashimov against Caruana was also quite lively but fizzled out to a draw. Of the others Wesley So kept a small pull, in by far the longest game of the round, but never really looked like winning.
The other games were all quite short with Black obtaining easy equality without much trouble.
Here is a summary of the first-leg games:
Note that nobody managed to win with White (left-hand column) in this, the first leg of the fourth round.
The two players who lost will now have to win with Black to get to the play-offs, a rare occurrence at this level, so the chances of Shirov or Laznicka proceeding to the quarter-finals are slim.
The following light notes show how they were second best in their matches today.
Alexei Shirov (2719) - Peter Svidler (2754)
Khanty-Mansiysk (World Cup 4.1) 30.11.2009
Gruenfeld Defence (D86)
1.d4 ♘f6 2.c4 g6 3.♘c3 d5 4.cxd5 ♘xd5 5.e4 ♘xc3 6.bxc3 ♗g7 7.♗c4 c5 8.♘e2 ♘c6 9.♗e3 0-0 10.0-0 ♕c7 11.♖c1 ♖d8 12.♗f4 ♗e5!?
12...♕d7 has been the most popular move over the years but the move played in the game was introduced by Ivanchuk only a year ago.
13.♗g3 ♗xg3 14.hxg3
Up to now 14.fxg3!? opening the f-file (but at the cost of damaging his own structure) had been played.
14...e5 15.♗d5 ♗e6!
Black is guarenteed counterplay against the centre whatever White now plays.
16.dxe5 ♗xd5 17.exd5 ♘xe5 18.c4 a6!
Preparing to undermine White's central edifice.
19.♖e1 b5 20.cxb5 axb5 21.♘c3 c4!
The most ambitious intending ...♘d3...
...but giving White access to this square.
23.♘xb5 ♕d7 followed by taking the exchange would also favour Black.
23...♕a7! 24.♘f6+ ♔h8 25.♕h4
25.♕a1 loses to 25...♕xf2+ 26.♔h2 ♖xa2
If 25...♕xf2+?! 26.♔h2 and only then 26...♔g7 White would have a strong attack following 27.♖f1
26...♘xc1? 27.♘h5+! gxh5 28.♕g5+ allows White to escape with a draw.
White's attacking gestures have not given him anything concrete and Black's positional trumps (good queenside pawns, dominating knight) now give him a clear (if not winning) advantage.
Otherwise 28.♖f1 ♘e5 29.♖f4 can be met by the materialistic 29...g5.
28...♖xd5 29.♕f6+ ♔g8 30.♖c3 ♘e5 31.♖f4 ♕xa2 32.♔h2 ♕e2 33.♕h4 ♖a6 34.g4 g5 35.♘xg5 hxg5 36.♕xg5+ ♖g6
V Laznicka (2637) - S Mamedyarov (2719)
Khanty-Mansiysk (World Cup 4.1) 30.11.2009
Quenn's Gambit Declined (D38)
1.♘f3 ♘f6 2.c4 e6 3.d4 d5 4.♘c3 ♗b4 5.♕a4+ ♘c6 6.e3 0-0 7.♗d2 a6 8.♕c2 ♖e8 9.a3 ♗d6 10.h3 h6 11.cxd5 exd5 12.♗d3 ♗d7 13.b4 ♘a7 14.♘a4 b6 15.♘c3 ♘b5 16.♘e2 ♘e4 17.a4 ♘a7 18.0-0 ♘c6 19.b5 axb5 20.axb5 ♘xd2 21.♕xd2 ♘b4 22.♘c3 ♘xd3 23.♕xd3 ♗e6
A battle of the knights against bishops that isn't clear-cut at all.
24.♘e5 f6 25.♘c6 ♕d7 26.f3 ♕f7 27.f4
This proves to be a slightly risky strategy as the pawns lack mobility and e3 is now a weakness that will require constant defence.
27...♖xa1 28.♖xa1 ♗d7 29.♖a2 h5 30.♔f2 h4 31.♔g1 g6
Laznicka bolsters his weak e3-pawn and threatens to capture on d5. However this move abandons the a-file for which he will later suffer.
Instead 32.♘xd5 can be met by 32...♗e6! (32...♕xd5 33.♕xg6+ ♔f8 34.♕xf6+ draws) 33.e4 f5, however White can then save himself with 34.♖e2! ♗xd5 35.exd5 ♖xe2 36.♕xe2 ♕xd5 37.♕e8+ ♔h7 38.♕d7+ ♔h6 39.♕e8 with a draw. So in view of the game continuation this would have been a better option.
32...♔g7 33.♕b1 ♗f5 34.♕d1 ♕e6 35.♕d2 ♖a8!
Taking the a-file turns out to be unpleasant for White.
36.♖e1 ♖a3 37.♖f1 ♖b3!
Slowly making progress whereas White is floundering.
39.♖a2 ♗b1! 40.♘xb1
Alternatives are not really any better: 40.♖a1 loses to 40...♗b2; and 40.♖xa3 goes down after 40...♖xa3 41.♕c1 ♖b3 42.♘xb1 ♕e4 43.♘c3 ♕d3 as White loses at least a knight.
40...♖xb1+ 41.♔h2 ♗c1 42.♕e1 ♕e4
The most precise although the ending after 42...♕xe3 was also promising.
Flashy and strong. For the record, also possible was 43...♗xe3 e.g. 44.♖xc7+ ♔f8 45.♖c8+ ♔f7 46.♖c7+ ♔e8 47.♖e7+ ♕xe7 48.♕xb1 ♗xf4+ 49.♔h1 ♕e4 and Black emerges with an extra pawn.
Naturally 44.exf4 ♗xf4+ also wins easily for Black.
44...♕e4 is simpler, but the text must have been so tempting!
Or if 45.♕xf2, then 45...♗xe3+ regaining the queen with a decisive advantage (virtually a mating net) in the pseudo-ending.
45...♔h6 46.♕d1 ♕e2!
Toying with his cornered prey.
Again if 47.♕xe2, then 47...♗xe3+ etc.
47...♕xe3 48.♕f1 ♕f4 49.♕d3 ♖a1
Everything is hanging. 0-1