Roger Federer admitted he was a relieved man after narrowly avoiding a fourth-round upset at the US Open on Tuesday.
The second-seeded Federer dug deep to defeat Igor Andreev 6-7 (5-7) 7-6 (7-5) 6-3 3-6 6-3 while number three seed Novak Djokovic also survived a five-set match to book spots in the quarter-finals. Andy Roddick joined the pair with a rout in the day's final match.
Federer is hoping to capture his fifth consecutive US Open title and had not lost a set in the first three rounds. In fact, Federer had won 21 straight sets at Flushing Meadows dating back to last year.
The 27-year-old Swiss, who has reached the semi-finals in each of the last 17 Grand Slam events, is seeking his 13th major championship.
But he was off the pace from the start, producing a number of poor shots before losing the first set on a tie-break after sending a backhand wide to give Andreev set point before another wayward effort saw the Russian take the upper hand.
The second set once again went to a tie-break. Federer raced into a 3-0 lead and although Andreev battled back to 5-6, the 27-year-old converted set-point at the third time of asking to level at one set apiece.
Federer, cheered on by the crowd, started to display his more customary form and comfortably won the third set 6-3 but Andreev continued to battle and took the encounter to a fifth behind an impressive service effort to win the fourth set by the same margin.
However, the number two seed raised his game to come through a tough contest that lasted just over three and a half hours when he claimed the fifth set after Andreev's attempted lob went long. He will now face qualifier Gilles Muller of Luxembourg in the last eight.
"He was dictating play," said Federer. "I don't remember that many (five-set matches).
"Being down a set and tiebreak in the second set there is danger written all over that situation," he said. "You just hope that it's going to turn your way. It did. So I'm happy."
Djokovic, one of the favourites to dethrone Federer this year, booked his place in the quarter-finals earlier on Tuesday but also needed five sets to hold off 15th-seeded Spaniard Tommy Robredo 6-4 2-6 3-6 7-5 6-3.
The reigning Australian Open champion, who was slowed down by an ankle injury earlier in the tournament, required treatment for a right hip problem in the second set and needed three hours, 25 minutes to reach the last eight.
It was the second straight match that the 21-year-old Serb had to fight back from a set down after he recorded a 6-7 (7-9) 7-5 6-4 7-6 (7-0) victory over 30th-seed Marin Cilic of Croatia on Sunday.
"The hip was a problem during the match but it was more exhaustion," Djokovic said. "The physio helped me a lot and it was a hot day. I don't think I would have felt that bad today if I didn't finish so late two nights ago."
A finalist here a year ago, Djokovic will now take on Roddick.
While Federer and Djokovic were pushed to the limit on Tuesday, the American barely broke sweat in a 6-2 6-4 6-1 rout of 11th seed Fernando Gonzalez from Chile.
Roddick won 53 of 62 points on his serve and faced only one break point against