Andy Murray beat highly-rated Spanish teenager Carlos Alcaraz 5-7 6-3 6-2 to reach the third round at Indian Wells.
Murray raced into a 3-0 lead but was pegged back to 4-4 and, after failing to take a set point on the Alcaraz serve at 5-4, lost the opening set.
But he levelled at one-set all - even serving underarm at one point.
Murray, 34, broke twice in the decider on the way to taking a captivating match against the 18-year-old in three hours and three minutes.
The victory will provide Murray, who is 121st in the men's rankings, with plenty of encouragement as he continues his latest comeback after four disrupted years following a major hip injury.