Chess Puzzle of the Week (184)

Gelbmann – Gyimesi
Siofok 1996
White to play

This position is taken from Unbeatable!: The Art of Defense by Jan Werle: my review will be published on British Chess News shortly.

Black has sacrificed a piece for an attack. How should White defend against the threat of mate on g2? I need a variation or two for a complete solution, not just the next move.