Roger Federer rallied from a two-set deficit and saved two match points to defeat Frenchman Gael Monfils 4-6, 3-6, 6-4, 7-5, 6-2 in the quarterfinals of the U.S. Open last night. It was the ninth time Federer has come back from two sets down and the win improved the Swiss Maestro’s record in night matches at Flushing Meadows to 28-1. At the beginning, though, the second-seeded Federer looked agitated and edgy, even getting into it with the chair umpire several times. Gusting winds were playing havoc with Federer’s trusty forehand and Monfils was playing out of his mind. Monfils saved two break points in the opening game and took control of the first set with a break in the fifth game. The 20th-seeded Frenchman parlayed service breaks in the first and ninth games of the second set to take a commanding two set lead over a clearly frustrated Federer. Federer committed 26 of his 44 unforced errors in the first two sets. The 33-year-old Swiss finally broke to open the third set, was broken in the fourth game, broke back and held out to climb back into the match. A pumped-up Federer roared as he broke to go up 2-1 in the fourth set, but he gave the break right back. A pair of unforced errors by Federer serving at 4-5 gave Monfils double match point. With nerves of steel, Federer reeled off four straight points as the crowd went nuts. Monfils double-faulted twice in the next game to drop serve. At that point it was all over but for the handshake. Federer held to take the set 7-5, and then limited an emotionally spent Monfils to just 11 points in the fifth to complete the stunning comeback in three hours and 20 minutes. “I still thought the finish line was far for Gael. I knew I could play better tennis,” Federer said. “I got off to a good start, so I was actually feeling alright, but then when I was down two match points, that’s when I wasn’t feeling so great anymore. I thought, ‘This is it. This is last point, man. Just go down fighting, don’t miss an easy shot and let him have it. It’s fine.’ But I served well and stayed in the match and somehow turned it around. I felt great in the fifth, though. I was really starting to play better and better as the match went on, and that’s a great feeling.” Federer, who improved to 8-2 against Monfils, hit five aces to six for the Frenchman. Monfils committed 10 double faults and 49 unforced errors, while Federer had just two double faults. The Swiss won 53 of 74 points at the net, Monfils 17 of 23. Federer takes on No. 14 seed Marin Cilic in one of Saturday’s two semifinals.