Andy Murray beat American Paul Goldstein 6-2 7-6 (7-4) in the second round of the Miami Masters, continuing his good early season form.
Murray was hampered by injuries at Indian Wells last week
The British number one broke Goldstein in the opening game and twice more in the first set to take control.
Murray served for the match at 5-4 in the second, but was unable to finish off the match as Goldstein broke back and eventually forced a tie-break.
Murray held his nerve to overcome some first serve problems to seal victory.
Murray admitted, however, that he was still struggling with lack of practice time following the ankle injury sustained in last week's quarter-final win over Tommy Haas at Indian Wells.
I did well to hang on in the tie-break but it's difficult when you haven't hit that many balls in the last few days
"I was out of breath and pretty tired to be honest," Murray said.
"I've only had about two-and-a-half hours practice over the last six days and the conditions here are completely different to Indian Wells.
"He fights hard in every match but I did well to hang on in the tie-break and it's quite difficult when you haven't hit that many balls in the last few days.
"I think it was more through my poor play that I let him back into it."
The victory for Murray means he will now face Robert Kendrick, who took Lleyton Hewitt's place in the draw after the Australian was forced to withdraw because of a back injury.
Murray, who had a first-round bye, is Britain's only representative left in the tournament after Tim Henman lost his opener to Guillermo Canas, and Alex Bogdanovic lost in qualifying.
Murray is in the same quarter as Andy Roddick, with Rafael Nadal potentially lying in wait in the last four.