Andy Murray saved seven match points in a 31-minute second-set tie-break before beating Philipp Kohlschreiber in the Dubai Championships quarter-finals.
The world number one needed eight set points to edge the German 20-18 in the tie-break and level the match.
It was the longest tie-break on the men's tour since the 2007 Australian Open.
Murray then raced to victory in only 30 minutes in the final set to win 6-7 (4-7) 7-6 (20-18) 6-1.
The Briton will play the winner of Lucas Pouille and Roger Federer's conqueror Evgeny Donskoy in the semi-final.
More to follow.