NEW YORK -- Trying to extend his stay at the U.S. Open, John Isner smacked a return winner, then pointed his right index finger toward the Louis Armstrong Stadium stands and circled his arm overhead, riling up the fans.
Two points later, sprinting so far he nearly reached the seats, Isner hit a forehand that closed a point, punched the air and then shook his fists, doing his best Jimmy Connors imitation. Minutes after that, Isner cupped his hand to his ear, basking in the chants of "U-S-A! U-S-A!"
The highest-ranked American man finally heard the adulation he'd been hoping for a couple of days earlier, when he lamented that so many spectators cheered so vociferously for his French opponent. What the 13th-seeded Isner failed to do in return Saturday was deliver a victory in the third round at Flushing Meadows, meaning only one U.S. man remains of the 15 in the field.
Isner even blamed those exuberant attempts to stir the crowd for his struggles down the stretch of a 6-4, 3-6, 7-5, 7-6 (5) loss to 22nd-seeded Philipp Kohlschreiber of Germany.
ACE™ Brand Pressure Point of the Match: Mini-breaks were of major importance in the fourth-set tiebreaker, and Kohlschreiber got the first one at 4-3, which he would ride to victory.
"I felt like I wore myself out getting charged up out there," Isner said after bowing out against Kohlschreiber in New York for the second consecutive year. "I used too much energy, and I shouldn't have done that. It was stupid on my part. So I was pretty gassed there. Had I kept it calm, I think I could still be out there right now."
The other American man in action Saturday, 20-year-old Jack Sock, was beaten 3-6, 7-6 (1), 6-1, 6-2 by No. 18 Janko Tipsarevic of Serbia.
So the last man from the United States left is Tim Smyczek, a 25-year-old from Milwaukee who got into the main draw thanks to a wild-card invitation from the U.S. Tennis Association and plays 43rd-ranked Marcel Granollers of Spain in the third round Sunday. If Smyczek loses -- a distinct possibility, considering he's ranked 109th and never before even made it past the second round at Grand Slam tournament -- it will be the first time with zero U.S. men in the round of 16 at the country's tennis championship, which was first played in 1881.
"I don't care," said Isner, who double-faulted to get broken in the last game of the third set, then was broken again while serving for the fourth. "I'm going to watch football for a while. That's all I care about."
A loss by Smyczek also would make 2013 the first season with no Americans in the second week of any of the four major tournaments.
Even if Smyczek wins, it still would be only the second time there was just one American in the fourth round at the U.S. Open. The other? In 2009, when Isner was the lone one in the second week.
All part of the recent decline of American men's tennis.
At Wimbledon this year, for example, no men from the United States even got to the third round. That hadn't happened since 1912 -- when no Americans entered the tournament.
Then came this news: The ATP rankings of Aug. 12 did not contain a single U.S. representative in the top 20. Never in the 40 years of men's rankings had that been the case.
This edition of the U.S. Open is the 40th Grand Slam tournament since an American man won one of the sport's four most prestigious titles, a record drought that dates to Andy Roddick's 2003 championship in New York. That sort of gap used to be unimaginable for the nation of Bill Tilden and Don Budge, John McEnroe and Jimmy Connors, Pete Sampras and Andre Agassi.
"Well, what shall I say? I think, yeah, it's bad luck," said Kohlschreiber, whose next opponent is 12-time major champion Rafael Nadal, a straight-set winner Saturday. "For sure, it's not great for the American history not to have a player in the second week. But you had so many good years."
There's a trio of Americans in the women's fourth round, because wild-card entry Alison Riske, who is ranked only 81st, eliminated 2011 Wimbledon champion Petra Kvitova 6-3, 6-0. The seventh-seeded Kvitova got her blood pressure checked by a trainer, then said afterward she had a virus and a fever.
"I've got a new confidence in myself," said Riske, a 23-year-old from Pittsburgh who is now based in College Park, Md. "I believe that I belong here."
There's no doubt the other two U.S. women who are left belong: No. 1 Serena Williams and No. 15 Sloane Stephens play each other Sunday with a quarterfinal berth on the line. Williams is seeking a fifth U.S. Open title and 17th Grand Slam singles trophy overall. Stephens is one of only three women to reach the round of 16 at every major tournament this year, and she beat Williams en route to the Australian Open semifinals.
Riske next faces Daniela Hantuchova, while other fourth-round matches set up Saturday are two-time Australian Open champion Victoria Azarenka against 2008 French Open champion Ana Ivanovic, and No. 21 Simona Halep against Flavia Pennetta. Caroline Wozniacki, the 2009 U.S. Open runner-up, was in action at night.
The final match on the day's schedule was 17-time major champion Roger Federer against 63rd-ranked Adrian Mannarino of France.
Men who reached the fourth round included No. 4 David Ferrer of Spain, No. 8 Richard Gasquet of France, and No. 10 Milos Raonic of Canada.
Raonic, the highest-ranked man in Canada's history, does not need to worry about the same kind of expectations that players such as Isner do.
"The relief, definitely, is there is obviously a lot more pressure on Americans," Raonic said. "I'm sort of doing a lot of stuff into unchartered territories, so people are very supportive of it, whereas I feel it's a little bit unfair to the American players. Everybody is expecting Pete and Agassi to be there on the top."