The last of 15 American men left in the U.S. Open on Tuesday when 20th-seeded Sam Querrey lost in the fourth round to No. 25 Stanislas Wawrinka of Switzerland 7-6 (9), 6-7 (5), 7-5, 4-6, 6-4 after nearly 4 1/2 hours of wind-affected play. Querrey's exit means no U.S. men reached the quarterfinals at Flushing Meadows for the second consecutive year -- something that never had happened before 2009 in the history of a tournament that began in 1881. 'I didn't feel any extra pressure or anything. I definitely wanted to win and keep the American men (in) -- keep the hope going,' said Querrey, who was broken in the match's last game. 'You know, I was close.' His exit also ensures there will be a record-low one appearance by an American man in the quarterfinals at any of tennis' four Grand Slam tournaments this season (Andy Roddick lost in that round at the Australian Open). Since 1925, when the French championships first allowed foreign competitors, the United States managed to place at least two representatives in Grand Slam quarterfinals every year. 'I mean, it's annoying that the Europeans are in the quarters every Slam,' Querrey said. 'We're trying.' There have been other negative signs recently for a nation that produced greats of the game through the generations such as Bill Tilden, Don Budge, Jimmy Connors, John McEnroe, Pete Sampras and Andre Agassi. U.S. men are in their longest Grand Slam title drought in tennis' 42-year Open era: No man from the country has won a major championship since Roddick at the 2003 U.S. Open, now a 28-tournament gap. The only longer span between U.S. Grand Slam titles was a 30-tournament shutout from 1955-63. Plus, there's this: Only two active U.S. men, Roddick and Robby Ginepri, even have reached the semifinals at a major tournament. When Roddick dropped to 11th last month, it marked the first time in the 37-year history of the rankings that the United States didn't have a member of the top 10. The U.S. Davis Cup team lost in the first round to Serbia in March, its earliest exit since 2005; if the Americans fail to beat Colombia later this month, they will fall out of the competition's World Group for the first time since 1988 and need to earn their way back into the top tier. 'The game's a lot different than it was in the '90s, when there were 15 countries playing. Now, every country is a contender,' Bob Bryan said after teaming with twin brother Mike to win Tuesday and give the U.S. a team in the men's doubles semifinals at Flushing Meadows. 'So, yeah, it's just a lot deeper. A lot of countries like Serbia rising to the top of the game and bumping America down.' With Querrey gone, Venus Williams is the only U.S. singles player still standing. She got to the semifinals by beating Francesca Schiavone of Italy 7-6 (5), 6-4 on Tuesday night in Arthur Ashe Stadium. That women's match didn't begin until after 6 p.m. because it followed Querrey vs. Wawrinka. Both Querrey and Wawrinka -- who upset 2008 U.S. Open runner-up Andy Murray in the third round this year -- were striving to earn a debut trip to a Grand Slam quarterfinal. And by joining his far-more-accomplished countryman, Roger Federer, in the round of eight, Wawrinka helped give Switzerland two quarterfinalists at a major for the first time. 'Roger, he's always in quarterfinals, (for) many years, so that's not something different,' said Wawrinka, a 25-year-old who is participating in his 23rd Grand Slam tournament. 'But for me, it's my first time, so it's something important for my career.' Wawrinka teamed up this summer with a new coach, Peter Lundgren, who was working with Federer when he won his first major title at Wimbledon in 2004. Lundgren has pushed Wawrinka to add variety to his game, and that helped against Querrey. Also key: Querrey's right leg began to cramp as the match dragged on. 'The last four games, he was really tired, and was really difficult for him to stay with his game,' said Wawrinka, who next faces No. 12 Mikhail Youzhny of Russia. 'He (changed) his game because he was tired.' Querrey certainly had his chances. 'He'll definitely have a feeling that this is a match he could have won,' said Querrey's coach, David Nainkin. 'He'll be disappointed that it got away from him.' In the first set, Querrey hit more aces and total winners than Wawrinka and held the only three break points of the set, at love-40 in the third game, but wasted them. Querrey also led 3-0 in that tiebreaker, then had a set point at 8-7 but couldn't convert. In the third set, Querrey went up a break and led 3-1, but got broken back to 3-all, then lost serve again in the last game, when he missed two volleys badly. 'Those are kind of the two shots I can look back, and that I remember, and I'm a little bummed about,' said the 22-year-old Querrey, who grew up in California and now calls Las Vegas home. 'The first one was kind of tough. The wind kind of got it behind my head a little bit. The other one was inexcusable.' Querrey lost in the fourth round for the second major tournament in a row, after also bowing out at Wimbledon in that round. 'Hopefully I can keep that up in the Slams,' he said. 'I think I can win that round-of-16 match, and keep winning matches after that.' Like the other U.S. men, he will have to wait till next year to find out. 