Andy Murray battled past world number three Ivan Ljubicic to reach the third round of the Madrid Masters.
Murray proved more resolute than Ljubicic in the deciding set
The Scot produced one of his best ever performances despite a lacklustre past month to seal a 6-4 3-6 6-3 win.
Murray, 19, broke the third seed in the ninth game of the opening set and stayed in control to move in front.
Ljubicic fought back to take the second, but Murray stepped up a gear in the third and punished a series of unforced errors by his opponent.
Ljubicic came into this match as the man in form, and when his big serve was working there was little chance of Murray breaking him.
But as the match moved into the deciding set Murray grew in stature while his more experienced opponent began to wilt.
Murray almost broke Ljubicic in the seventh game, only for two close line calls to save the Croatian, who retained his Vienna title on Sunday.
But in Ljubicic's next service game he took his chance, trading big forehands with patience until Ljubicic cracked and made the error.
Murray has crashed out in the first round of his last two tournaments, but he held his nerve to serve out the match with an ace.
"It is a huge victory for me against a guy ranked number three in the world," said the world number 19.
"On top of that I beat him on his preferred surface. Today's win gives me confidence that I can go on to secure my place among the best players.
"He's one of the best indoor players in the world so it is a good benchmark.
"I have definitely got more confidence than I had earlier in the year but I can still play better."