Maybe, he should have decided on 27...Ne4! 28.Rfc2 Qb8 (28...Nxc5 29.Nxc5±) 29.Nd4 Rxc5 30.Rxc5 Nxc5 31.Rxc5 (31.Nxc6?! d4 32.Qa3 Qb3! (32...Qb6 33.Ne7+ Kh8 34.Nd5 Qb8 35.Qxc5) 33.Qxc5 d3) 31...Be8 32.Rc1!? – in this position, White has the advantage, but it is not apparently how he can crack Black’s defences.

Now, Black does not obtain sufficient counterplay.

The black king is blocked in by its own pieces, and White seals it up even further:

More tenacious is 17...gxf6 18.exf6 Rd8! (he loses after 18...Bd6 19.Rd4! – the rook goes to h4), preventing the transfer of the white rook to the kingside. However, Black’s position is still difficult, of course, as his king is exposed, and his dark squares are creaking.

The king is protected by the enemy pawn on g7, a well-known defensive device. Black would like to capture it later, when things have simplified, and his king is not under threat.

On the way to help its neighbour. The white pawn is heading to h6, to secure a decisive advantage in the endgame, as the black king will be completely tied down to covering the passed pawn.

White solves his main task at this moment, organising a blockade on c4, for which purpose his queen retreats to b3.

White has been ready for a queen exchange for some 20-23 moves, ever since he finished the march of his rook’s pawn! Black had to keep the queens on, choosing, for example, 33...Qg4 – White would face greater technical problems there.

Black resigned.

Exploiting his numerical superiority on the queenside, Black sacrifices a pawn to create a passed pawn.