What a move 11.a3!! Aronian-Carlsen_Norway Chess 2017

[Jeroen]

Bg4 f3 ef3 gf3 Bh5 Qe2

The move Bg4?! is very cooperative, just helping white. Why should black give up the e4 point and free the bad black-squared Bc3?

[Lyudmil Tsvetkov]

11.a3 was a huge surprise for Carlsen and had many pitfalls. Not easy with only 1:40 for 40 moves to select the best lines here. So in practical play between humans 10.a3! is surely for preference (and the game result proves it).

11.c5 is a typical engine blocking move (grab space) and I can imagine Aronian will not like it. 11... e5 is not forced, black could also try the typical undermining move 11... b6. After 36 ply SF on my slow notebook just gives 0.06 in white's favour after this move.

Aronian is the best prepared player in the world, with original ideas and deep insights. If 11.c5 is really best - what you suggest - he would have played it. It is rather odd to see a 2180 player claiming he knows better than Aronian, who probably has spent a huge amount of time on this position.

we are not talking of psychology, but of objectively bst moves.
I do not think psychology plays such a big role at this level; if Aronian thought c5 os best, he certainly would have played it.

the line you suggest, 11...b6, quite probably loses very quickly after cb6:

[d]r1br2k1/3nqppp/pPp1pn2/3p4/1b1P4/1PN1PN2/P1BB1PPP/R2Q1RK1 b - - 0 2

black is left with a backward c6 pawn along a semi-open file, isolated a6 pawn, worse activity, those certainly should suffice for a win, but really, I do not have any time to analyse now, might look at it at some point later.

[Lyudmil Tsvetkov]

Bg4 f3 ef3 gf3 Bh5 Qe2

The move Bg4?! is very cooperative, just helping white. Why should black give up the e4 point and free the bad black-squared Bc3?

one way or another, after Re1, defending e3, whether black plays Bg4 or something else, white is able to push f2-f3/f2-f4, getting rid of the nasty clamp of the e4 pawn, after which white has nothing to fear on the king side, while on the queen side white has big advantage.

[BrendanJNorman]

Bg4 f3 ef3 gf3 Bh5 Qe2

The move Bg4?! is very cooperative, just helping white. Why should black give up the e4 point and free the bad black-squared Bc3?

Because the engine said to play ...Bg4?

[Jeroen]

This is very superficial analysis, white surely isn't safe on the K-side yet after f2-f4 (opening up the g-file with g7-g5 comes to mind).

Meanwhile, from a human standpoint, by playing Bg4 f3,exf3 gxf3 you have accomplished the following:

A) you gave up the black stronghold on e4, which clamps white on the K-side
B) you gave away black's advantage on the K-side
C) you opened the g-file, which doesn't look to be to black's benefit
D) you give white an additional plan with e3-e4
E) you give Bc3 more scope, in the initial position it has almost no active possibilities
F) Bc2 now suddenly has a nice open diagonal

To black's benefit: his bishop has now more scope; he might trade the white squared bishops by Bg4-h5-g6, weakening the white squares; black now has the open e-file.

My SF insists that black has a clear edge after Bh3 (instead of Bh5, but, admittedly, with slow hardware). That looks exaggerated, but one can not ignore the opinion of the strongest engine. To me it looks that black cannot create any threats on the K-side, but the position is complicated and when white doesn't manage his a4/b4/b5 minority attack or his e3-e4 push in the center, the position looks very unclear. Certainly not 'better for white'.

[whereagles]

Lyudmil, history of chess, or any other sport at the top level, is ripe with victories and losses owing to psychology. Trust me, I've been there.

[Jeroen]

The purpose of a game of chess is winning. Which is what 11.a3! did. In human games the objectively best move is sometimes not the best (in a sense of winning).

11.c5 surely is a good move (in the Chebanenko Slav it often is), but to claim that it is better than 11.a3 is still open to debate. I am not convinced. For a human the position with a cut off queen on a3 is extremely difficult to play. Hence, in a human game a fully prepared 11.a3 very likely has a better chance of winning the game than 11.c5.

The best solution is, to ask Aronian what his opinion is on 11.a3 and 11.c5.

[whereagles]

Lyudmil, chess is full of victories and losses from psychology. Or any other top level sport for that matter. Trust me.. ive been there.

[Jeroen]

The more I look with SF, the more I am liking black after Bg4 f3,exf3 gxf3,Bh3:

* Black follows up with Ng6 and/or Nh5, which discourages e3-e4, as there will land a black knight on f4;
* White's minority attack on the Q-side is going nowhere yet;
* In the meantime black plays Nh5, his rook to e8 (might even double rooks on the e-file in the next few moves) and then f7-f5, putting maximum pressure on white's position.

No doubt SF would crush Lyudmil in this position .

[IQ]

I already proved a3 is a forced draw, so why insist further?

You proved no such thing.

c5, on the other hand, gives white excellent winning chances.

Better than a Pawn up, rook penetrated on the seventh, active king, bishop against knight? Sorry, neither did you make a convincing case nor could you - proving that c5 gets a better position than the one discussed here after 28. e4 is practically impossible.

analyses on youtube [in reference to Peter Svidlers analysis] and similar channels are usually low quality.
I looked at chesspro.ru, and they do not have a clue about what is going on in that game, neither about if a3 gives any side advantage, nor about anything else. and that is supposed to be the highest quality site around.

I could tell you who's analysis are generally low quality but that would be impolite. I could also tell you who's analysis is superficial, full of generalitities and misplaced arrogance. But I won't.

... but what is obvious is a3 is bad move....

Every one of the Super-GMs playing in Stavanger would give an arm and a leg to get the position you call a draw. Even if not winning it's a complex position with lasting white pressure and black has to find a myriad of only moves to stay in the game.

Oh and one final thing in your claimed "drawn" position after: 28.e4 Ra1+ 29.Ke2 Ra4 30.Kd3 f6 31.Rc7 Ra6 32.Bf4 e5 33.dxe5 Kd8 34.exf6 gxf6 35.Ke2 Nxc5 ... how about 36 Kf3... seems to me white has excellent winning chances, if he is not winning outright.

My conclusion: Aronians Bc2 and his later a3 are fantastic novelties posing black real problems, leading to exciting games and will entertain theoreticians for quite some while. What more can one expect from openin? Probably not much, except if your mame is Lyudmil Tsvetkov.