White has a good position in the centre, but his king is on an unpleasant diagonal, where it faces threats of checks. This is felt especially in conjunction with the position of the Bf4, which is currently cut off by the e3-pawn from the diagonal a5-e1. This circumstance could be exploited with the surprising...

The game went 15...Qb5+ 16.Kd2 Qa5 17.Ke2 Qa6+ 18.Kd2 Qa5 19.Ke2 Qa6+, with a draw by repetition.

With this move, Black lures one of the white pieces to c2.

On 17.a3, Black wins immediately with 17...Bb4+!.
If White defends the king with 17.Qd3, then after 17...Qa5+ 18.Ke2 Nxa1 19.Rxa1 Qa4, he not only loses the exchange, but also concedes the c-file, which gives Black a decisive advantage.

After 18.Qxc2 Bb4+ 19.Kd1 Qf1+, White is mated.

Black is winning.

Both sides have very exposed kings, but it is Black’s move and he has a queen pointing at the white king. The rook on f3 stops a deadly check on f2, so the solution is easy to find:

White resigned.

How can the rook ‘hurdle’ the knight and give a deadly check on d8? One needs to find the square where the knight will be most effective in the attack, even if that square is empty:

The knight is invulnerable (24...exf5 25.Qf6), and by comparison with other squares to which it could have jumped, from here it attacks g7 and e7.