Grit was not going to be enough to get Maria Sharapova past No. 1-seeded Caroline Wozniacki of Denmark on Monday, especially not after the Russian conceded nine double-faults - including three in a row - and a total of 36 unforced errors.
Wozniacki, the 2009 runner-up, wrapped up a 6-3, 6-4 fourth-round win over Sharapova, who has failed to make it even as far as the quarterfinals at Flushing Meadows since winning the 2006 title.
Doing ''what she does best,'' as Sharapova herself put it, Wozniacki got to nearly every ball and hammered it back, stretching points on and on and on until her opponent missed the mark.
''I felt like I was playing well out there,'' Wozniacki said, then made sure everyone understood a key concept by adding, ''I made her do those errors.''
Indeed, she did. Rare is the opponent who can trade powerful baseline groundstrokes with three-time Grand Slam champion Sharapova and figure out a way to put her on the defensive, but that's exactly what Wozniacki managed to do as early evening shadows crept across the blue court in Arthur Ashe Stadium.
''When she had the opportunity to step in,'' the 14th-seeded Sharapova said, her voice a barely audible monotone, ''she took it and went for her shots.''
It's the first victory for Wozniacki in three career meetings against Sharapova, but they hadn't met since 2008. In that time, the 20-year-old Wozniacki has grown as a player and built a huge supply of confidence, thanks to her Grand Slam final debut in New York and, most recently, her 18-1 record since Wimbledon.
''I've improved a lot, not only physically, but also I believe in myself more. I believe I can do it,'' said Wozniacki, who is ranked No. 2 but received the top seeding at the U.S. Open after No. 1 Serena Williams withdrew. ''Also, I think I can mix up my game a little bit more.''
Wozniacki has lost only 10 games so far; no one has conceded fewer en route to the U.S. Open quarterfinals since 1999. But here is what might be the most remarkable statistic of all: After making only 10 unforced errors against Sharapova, Wozniacki has made 40 in four matches, and her opponents have made 123.
''Obviously,'' Sharapova said, ''she's at the top of her game.''
Wozniacki carries a 12-match winning streak into her quarterfinal against 45th-ranked Dominika Cibulkova of Slovakia, who eliminated 2004 U.S. Open champion Svetlana Kuznetsova of Russia 7-5, 7-6 (4).
The 5-foot-3 (1.6-meter) Cibulkova, a semifinalist at the 2009 French Open, was treated for a left leg problem between sets but still managed to scurry around, covering ground, to improve to 2-8 against top-15 players this season - with both victories against the 11th-seeded Kuznetsova, who double-faulted 10 times Monday.
Asked to assess Wozniacki, Cibulkova said admiringly: ''She's really consistent, and she can keep the level that she's playing the whole match.''
The other quarterfinal on that side of the draw will be No. 31 Kaia Kanepi of Estonia against No. 7 Vera Zvonareva, who overwhelmed 38th-ranked Andrea Petkovic of Germany 6-1, 6-2 Monday night. Russia's Zvonareva, the runner-up at Wimbledon in July, reached the U.S. Open quarterfinals for the first time.
Earlier, Kanepi did the same by coming back to defeat 2009 U.S. Open semifinalist Yanina Wickmayer of Belgium 0-6, 7-6 (2), 6-1.
After getting off to a terrible start against the 15th-seeded Wickmayer, Kanepi turned the match around completely, then explained of her play down the stretch, ''I was, like, in the zone or something.''
Third-seeded Novak Djokovic might have said the same about his own performance Monday, when he reached the men's quarterfinals at the U.S. Open for the fourth consecutive year by outclassing No. 19 Mardy Fish 6-3, 6-4, 6-1. Fish's exit leaves one U.S. man in the tournament, No. 20 Sam Querrey, who plays his fourth-round match Tuesday against No. 25 Stanislas Wawrinka of Switzerland.
Serbia's Djokovic, the 2007 U.S. Open runner-up and 2008 Australian Open champion, next faces No. 17 Gael Monfils, a 6-4, 7-5, 7-5 winner over Richard Gasquet in an all-French matchup.
Five-time U.S. Open champion Roger Federer beat 13th-seeded Jurgen Melzer of Austria 6-3, 7-6 (4), 6-3 Monday night to reach the quarterfinals at a 26th consecutive Grand Slam tournament and set up an intriguing rematch with Robin Soderling.
No. 5 Soderling of Sweden is the man who ended Federer's streak of 23 consecutive Grand Slam semifinals with an upset in this year's French Open quarterfinals.
''He's always been a dangerous player,'' Federer said in an on-court interview. ''This is obviously a tough draw for me in the quarters, playing Robin.''
Playing in front of a star-studded capacity crowd, Federer delivered a crowd-pleasing performance that included 41 winners.
''Haven't lost a set, so obviously, I'm very happy,'' Federer said. ''It doesn't matter too much how you play, really. I'd love to play wonderful every time I come on the court. Guys make it tough. They play and make it the way you don't want it to be.''
Federer got some help from the net in the second-set tiebreaker, twice hitting balls that hit the tape and trickled over to end points.
''It's a pity that I didn't win at least one set. I think I deserved the second set. I think I was the more dangerous player,'' said Melzer, a semifinalist at this year's French Open. ''You couldn't be more lucky in a tiebreaker than was in this tiebreaker.''
The first net-cord point came at 1-1, when Federer hit a forehand approach shot as he moved forward. The ball danced along the top of the net before falling over. Melzer threw his head back in dismay. The second came at 4-4, off a forehand return, and Melzer wouldn't earn another point in that set.
When Federer, owner of a record 16 Grand Slam championships, smacked a cross-court forehand winner to close the tiebreaker, he screamed, ''Come on!'' - and Melzer looked up at his entourage and yelled, too.
''I wasn't happy with my fortune. Let's put it that way,'' Melzer said later.
Federer's take? ''Tiebreakers are always crucial,'' he said.
Recovering quickly from that, Melzer broke serve to open the third set. But his 1-0 lead lasted only briefly, because Federer broke right back to 1-1, then again to go ahead 4-2.
Federer and Melzer, both 29, have known each other for more than a decade, and they even played doubles together as juniors. But they never faced off as professionals until this summer at Wimbledon, where they also played in the fourth round - and Federer also won in straight sets.
Now Federer will take on another familiar foe in Soderling, who advanced earlier Monday by eliminating No. 21 Albert Montanes of Spain 4-6, 6-3, 6-2, 6-3.
Looking ahead, Soderling said: ''It's always a very nice feeling to play against the world's best. It's matches like that you train for. It's matches like that I've been dreaming of playing since I started playing tennis - playing at the big courts in the big tournaments. It's very fun.''
Federer owns a 12-1 career record against Soderling, but that lone loss came in their most recent meeting, at Roland Garros on June 1. Before that, Federer had won 117 matches in a row - 117! - in the first five rounds at major tournaments, dating to a loss to Gustavo Kuerten in the third round at the French Open on May 29, 2004 (Federer advanced twice when opponents withdrew).
Federer has won 44 of his past 45 matches at the U.S. Open, the only defeat coming in last year's final against Juan Martin del Potro.
Soderling will try to hand Federer another rare loss.
''Well, I played him so many times; I know his game and he knows mine,'' Soderling said. ''I'm pretty sure how I need to play to have a chance to win.''
Sharapova accumulated eight break points against Wozniacki, but converted only one.
''That's pretty bad, to say the least,'' Sharapova acknowledged.
Still, considered one of the toughest competitors on the women's tour, Sharapova rarely departs quietly, and she ratcheted up her trademark, high-octave shrieks right along with her skilled shotmaking Monday.
''I knew that she wasn't going to go away,'' Wozniacki said. ''I knew she was going to hang in there and keep fighting till the end.''
Sharapova saved Wozniacki's first match point with a gutsy volley winner while serving at 5-3 in the second set. That was part of some strong net play: Sharapova won 16 of 18 points when she pushed forward, but that efficiency would not suffice.
Sharapova delivered 12 of the match's first 15 winners. But she also was responsible for 12 of the first 15 unforced errors.
When Wozniacki served for the first set, Sharapova held a break point at 30-40, and they played a 24-stroke point that ended with Sharapova pushing a backhand long. Later, on Wozniacki's third set point, there came a 26-stroke exchange that concluded with - yes, that's right - another errant backhand from Sharapova.
''That's great tennis, when there's good rallies. I think it's good for the crowd, as well,'' Wozniacki said. ''It just feels great when you feel like you're hitting the ball right - it's in the middle of your racket. The ball does whatever you want it to do.''
