I dont see why he would prepare d4 with c3 and then play d3? That seems to defeat the purpose of c3.

sometimes, when the black bishop is on g7 it is better to play d3 and to not open the diagonal for it. that way the h8-a1 diagonal stay closed.

It does seem anti-thematic, though. After 4.d4 cxd4 5.cxd4 Bg7 6.Be3 followed by 7.Nc3, White has the big centre he was aiming for...

(??) After Black plays ...d6, it certainly is in White's interest to prevent the f6-knight coming in at g4. But more thematic would have been 8.f3, which would have been quite good here, as it protects the e-pawn.

Instead of this exchange, White might have considered 10.Qa4, forking the loose e4-knight and c6-pawn. If 10...Qd5 11.Bc4 Qd6 12.Bxf7+ Kxf7 13.Qxe4 is a possible line.

Instead of exchanging knights on d2, White might have tried 11.Bd3 to drive away the e4-knight. If Black elects to protect it where it stands, then 11...Bf5 12.g4 or 11...f5 12.Bxe4!? fxe4 13.Nd2 (Bf5 14.g4). If the knight retreats, White can develop at his leisure with a playable game.

White's 18th was an unnecessarily weakening move. Black's reply shows one aspect of this, developing a piece with a gain of tempo. But Black could almost as well have played 18...axb3 e.p. 19.axb3 Be3 20.Kb2 e4, with a considerable attack on the Q-side. A possible course of the attack might have been 21.Ra1 b4 22.Rxa8? Rxa8 23.Rc1 Ra3 24.Bc4 Bxc4 25.bxc4 Bxc3+ 26.Bxc3 Rxc3 27.Rxc3 bxc3 28.Kxc3 Kd6 and Black has retained a pawn plus into a pure pawn ending.

You can't take a pawn e.p. when it's only moved one square.

Lashing out. Unfortunately for White, exchanging opposite coloured squared bishops isn't a realizable plan. In fact White doesn't have many moves available at all. 24.fxe4 (...Bxe4+) loses a pawn; and 24.f4 leaves Black with a central passed pawn. White is very nearly in Zugzwang.

28.a3 looks sensible, and would have averted Black's neat tactical shot. Now (for those who are wondering) 29.Bxd4 Rxb4+ 30.Bb2 a3 31.Kc1 Rxb2 32.Rxb2 axb2+ 33.Kxb2 g5 (-+).

What could White have played instead? 30.Re2 c5 doesn't look too appetizing for White. 30.Rd2 Kxe7 transposes into the game. Apart from that, White's bishop has no moves (30.Bc5 Bxc5 31.Rxc5 Rxb4+). But after the text move, White will lose another pawn or the rooks will come off leaving Black with an easily winning pawn endgame.

Despite resisting stoutly, White was fighting a losing battle for the final two-thirds of the game.