Sports

Fish swims into Round of 16 to face top-seeded Federer

American Mardy Fish outlasted No. 16 Gilles Simon 6-1, 5-7, 7-6 (5), 6-3 in one of the later U.S. Open matches in recent memory, ending when Simon’s volley sailed long at 1:09 a.m.

Fish’s reward? A Round of 16 date with top-seeded Roger Federer tomorrow.

“It’s everything. This is why we play, to play matches like this, so it’s pretty special,” Fish said. “This is a special place, obviously. Playing here, you want to take it all in, you want to win so badly.’’

Fish made Federer work for a 6-3, 7-6 (7/4) win in the Cincinnati-1000 two weeks ago. What does he need to do break through?

“I have no idea,” Fish said. “A lot more than I did [last night].’’

In a marathon match that went more than three hours, it was a ten-minute span that may have decided it. Down a mini-break in the tiebreaker, the ailing Frenchman — clearly not fully healthy, tried to force Fish to serve wide. But Fish got a service winner, got a second wind and followed with a strong third set.

“It’s tough. I know he’s not feeling 100 percent. Sometimes its even tougher to play guys like that, even tougher to keep your concentration,’’ said Fish. “Apart from the serve, he seemed to play pretty well, so I wasn’t quite sure what was going on. It made for a long night.’’

Fish missed over two months due to a problem with his heart, hospitalized after Miami-1000 when his heart rate increased to three times its normal resting rate. He underwent a cardiac catheter ablation on May 23.

His father Tom – a tennis teaching pro – was in the stands for his 60th birthday, and the hearty souls who stuck around at Arthur Ashe Stadium serenaded him with happy birthday. His son gave him a great present.

* Jack Sock still has a long way to go. At least in the rankings.

Sock packed the Grandstand court with 6,100 revelers rooting on the 19-year-old stud from Kansas via Nebraska. Chants of “Let’s go Sock’’ thundered through the mini stadium that will soon be demolished.

But after bringing the frenzied throng to its feet in full roar after he survived a second-set tiebreaker to even the match, Sock disintegrated in the heat.

Sock’s U.S. Open run ended yesterday in the third round, beaten by the Spanish clay-courter Nicolas Almagro 7-6 (7-3), 6-7 (7-4), 7-6 (7-2), 6-1 in a three-hour slugfest. It was the first match at this year’s Open in which the first three sets were all tiebreakers. The atmosphere was electric, with the Spaniard even jawing with a front-row fan.

“New York for the Open is definitely the best possible scenario to play tennis in front of the home crowd,’’ Sock said. “That match, the energy from the crowd was unbelievable. I love playing on that court [Grandstand]. The fans were right there into the match.’’

Sock turned pro a year ago and won his first-round match here last year after winning the U.S. Junior Open in 2010. He will move up in the rankings from 242nd to roughly 211st with his third-round showing. But he’s got the big serve and big forehand to be a top-10 guy, just needing more match experience, better fitness and more consistency. Though Amalgro was playing just his first hardcourt tournament of the year, he proved too savvy.

Sock, his white cap soaking wet, needed two medical timeouts as a trainer worked on his forearm, but denied he was cramping.

“It gets tight when I play a lot of tennis,’’ Sock said.

Sock is working with Andre Agassi’s former fitness guru in Las Vegas, the renowned Gil Reyes.

After losing the first tiebreaker, Sock romped in the second tiebreaker but then got destroyed in the third-set tiebreaker, 7-2.

“Everything feels better now, and I definitely feel closer to the next level,’’ Sock said. “I’m definitely going in the right direction.’’

* Because of CBS’ daytime coverage, Andy Roddick is forced to play in the day heat in possibly his final match. Roddick, who likes the night atmosphere better because of the wilder crowds and cooler conditions, will face Italy’s Favio Fognini at about 1:30 p.m. todayRoddick, seeded 20th, announced on his 30th birthday last Thursday this was his last tournament. … Britain’s lefty 18-year-old Laura Robson, who is on the roughest side of the draw, already has knocked off two seeds in Kim Clijsters and Li Na and now faces defending Open champion Samantha Stosur today.

* Roger Federer said after his victory over Fernando Verdasco that he has come down with a case of the sniffles due to “the air conditioning in this country”.

marc.berman@nypost.com