Murray came through a feisty encounter with Llodra
British number one Andy Murray had to dig deep to reach the third round of the US Open with an erratic 6-4 1-6 7-5 7-6 (9-7) win over Michael Llodra.
Murray began well but was outplayed in the second set before raising his game at a vital moment to snatch the third.
The Frenchman twice went a break up in the fourth set but Murray took it to a tie-break, saving two set points before eventually sealing a hard-fought win.
Murray, the sixth seed, will play Austria's Jurgen Melzer in the last 32.
"(Llodra) is such a tricky guy to play against, he is very good at the net," said the 21-year-old Briton.
"It was a tricky match and I knew it was going to be tough but I am glad I came through. I think everyone feels a bit of pressure in those tense moments.
"I think he served well on those big points but he did miss an easy shot and I managed to get a few returns back."
After the ease with which he dispatched Argentina's Sergio Roitman in the first round this match should act as a wake-up call for Murray, who was lucky not to be taken to five sets by an opponent he had been expected to beat comfortably.
It all looked straightforward enough for the Scot in the early stages when he broke Llodra in only the third game of the match, and that proved enough to give him the first set.
Llodra, a doubles specialist who is ranked 38 in singles, was charging to the net at every opportunity and played some brilliant shots but Murray seemed to have his number at that stage.
The situation changed drastically in the second set, when Murray's weak second serve allowed the Frenchman to continually attack him.
Murray's first delivery was also far too inconsistent and, as a result, Llodra broke twice to level the match.
Things were a lot tighter in the third set before Murray struck at 6-5, taking advantage of an uncharacteristic wobble from his opponent to break to love and snatch the set.
There were still plenty of twists and turns to come, however, as Murray was still serving poorly and was also clearly frustrated by some of the calls that were going against him.
Twice Llodra went a break up only for Murray to raise his game and reply instantly and, after Murray saw a match point come and go at 6-5, that pattern continued into the tie-break as both players mixed brilliant shots with some inexplicable errors.
It was a good win - he's a tough guy to play against and he's had his best year ever on tour
Andy Murray on Michael Llodra
Serving at 5-3 after a brilliant cross-court winner, Murray appeared to have the match within his grasp but a double-fault handed the initiative back to Llodra.
Llodra then had two chances to take the match to a deciding set, one on his own serve, but sent a backhand into the net to allow Murray to level at 7-7.
Another mistake by Llodra handed Murray his second match point and this time the Briton made no mistake, powering a forehand down the line to set up a smash to clinch victory.
Murray's resolve was admirable but he will need to iron out his inconsistencies, particularly on serve, when he faces Melzer, the world number 48.
Melzer, who Murray is also likely to face in Britain's Davis Cup tie at Wimbledon in September, trounced Jiri Vanek of the Czech Republic 6-0 6-2 6-2.
If he gets through his next two matches, Murray is scheduled to meet world number four David Ferrer in the last eight, and world number one Rafael Nadal in the semi-final.
But the 22-year-old says he would be foolish to look that far ahead.
"The guys that I'm playing before are not guys that I'm 100% expected to beat if there's a chance I can lose the match," Murray said.
"They're really top players so there's no point in looking ahead.
"You understand what's going on in the draw, you know which half of the draw you're in and who the top seeds are, but it doesn't make me start looking into semis or quarter-finals.
"I've only made the quarter-finals of a Grand Slam once and, you know, I'm not good enough to do that."
Andy's brother, Jamie Murray, saw his bid for success in the men's doubles end at the first hurdle.
Murray and Max Mirnyi of Belarus, the 14th seeds, were edged out 7-6 (7-1) 7-6 (10-8) by Slovakia's Micah Mertinak and Lovro Zovko of Croatia.
And Anne Keothavong, who like Andy Murray is into the last 64 of the singles, was knocked out in the first round of the women's doubles.
The Londoner and her Russian partner Anastasia Pavlychenkova lost 6-3 6-4 to Lucie Safarova of the Czech Republic and Italy's Mara Santangelo.
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