Updated

Setting aside a disagreement with the chair umpire and a whopping 75 unforced errors, 23rd-seeded Mardy Fish of the United States outlasted a hobbling Gilles Simon of France 6-1, 5-7, 7-6 (5), 6-3 to win a third-round U.S. Open match that ended past 1 a.m. Sunday.

By beating the 16th-seeded Simon, who repeatedly stretched his leg muscles and hit serves slowly, Fish reached the round of 16 at Flushing Meadows for the third consecutive year. He's only made it to the quarterfinals once in 12 appearances, losing to Rafael Nadal at that stage in 2008.

This time, Fish's reward is a matchup against top-seeded Roger Federer, who has won five of his record 17 Grand Slam titles at the U.S. Open.

Asked during an on-court interview what he'll need to do to get past Federer, Fish responded: "I have no idea right now, to be honest. A lot more than I did today. But we'll try to rest as best we can and see what we can do."

The 30-year-old Fish missed about two months this season because of an accelerated heartbeat and had a medical procedure in May.

After the 3-hour, 3-minute match, he did not appear at a news conference; the tournament said he was getting treatment, but didn't give any specifics.

Still, on court, Fish was fresher than Simon, especially at the end, reeling off the last four games — including breaking at love to go ahead 4-3 in the last set.

"I know that he's not feeling 100 percent, and sometimes it's even tougher to play guys like that, to keep your concentration," Fish said. "Apart from the serve, he appeared to be playing really well. ... Made for a long night."

Sure did.

There were plenty of drawn-out points, as if they were slogging their way through a match on red clay. Fish put together a 67-20 edge in winners, but also made many, many more miscues, 75-31.

They began a tad past 10 p.m. on Saturday night, which was the 60th birthday of Fish's father — he was serenaded with a chorus of "Happy Birthday" by spectators at the end.

"This is probably a good gift," Fish said, smiling.

He was in a far worse mood earlier in the evening.

Fish was up a set and a break but couldn't pull away against an opponent who appeared to be struggling with bothersome legs. Simon kept propping a heel on his changeover chair to stretch out his hamstrings when switching sides or hopping around as though trying to loosen the muscles. His service speeds were rather slow, averaging under 95 mph on first serves and about 80 mph on second serves.

Simon said afterward he didn't have a leg injury.

"I was just tired from my two matches before. They were long. And it's hard to recover because I had to run a lot. It starts to be painful in the legs," said Simon, who played five sets in the first round, then four in the second.

"The first match was very hard. The second one was hard also and didn't allow me to recover before this one," Simon added. "Already at the beginning it was difficult, so of course it's getting worse and worse on the court. But it's part of the game. I have to be in better shape."

Fish had his own issues, getting into a dispute with chair umpire Carlos Ramos over the way a line call was handled.

In the 10th game of the second set, Simon hit a shot that appeared to land long in the middle of an exchange. Fish continued the point and eventually lost it, then pointed out a mark beyond the baseline to Ramos.

"I can't do your job and mine at the same time," Fish told the official, who responded: "Mardy, I'm telling you, I saw the ball good."

By rule, Fish would have had to halt play during the point to challenge it; a TV replay showed the ball did, indeed, land long.

Fish lost that game and might have allowed his frustration to leak into the next one, too, because he quickly fell behind love-40 and wound up getting broken when he dumped a backhand into the net to trail 6-5.

The conversation between Fish and Ramos continued at the ensuing changeover — sort of. With the loud music that blares over the arena loudspeakers during breaks, Fish told Ramos: "I cannot hear one word you're saying, so all you're doing is yelling. I cannot hear you at all."

And that was that.

Simon then came out and served out the set, which ended with three consecutive missed forehands by Fish.

The American had a chance to get up quickly in the third set, holding three break points while ahead 1-0, but he failed to convert any of them. After Simon held there, he stood with his back against the wall near a baseline, grabbing his left toes and pulling that leg behind his back to stretch his thigh muscle. At the opposite end, Fish tossed his racket to the court.

He showed some more anger in that set's tiebreaker, leaning forward and screaming at himself after Simon whipped a running backhand passing winner on a full sprint to take a 3-1 lead.

Maybe that got Fish going, because he won the next two points and later used a backhand volley winner to close the set at 12:35 a.m., 2½ hours after they started playing.

Fish did not need a lot more time to end things.

___

Follow Howard Fendrich on Twitter at http://twitter.com/HowardFendrich