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.
No men’s tour-level match has featured a tie-break with more than 38 points since 1991 – six have finished 20-18.
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, who said he had “never played a tie-break like that in my life”, will face number seven seed Lucas Pouille in the last four on Friday.
The Frenchman beat Roger Federer’s conqueror Evgeny Donskoy 6-4 5-7 7-6 (7-2).
Fernando Verdasco and Robin Haase will meet in the other last-four tie.