NEW YORK — Teenager Kei Nishikori became the first Japanese man to reach the U.S. Open's fourth round in the 40-year Open era, upsetting fourth-seeded David Ferrer of Spain in five sets Saturday night.
Nishikori, ranked 126th, could have ended things earlier, but he wasted a two-set lead, then needed three match points to wrap up the 6-4, 6-4, 3-6, 2-6, 7-5 victory.
He broke Ferrer in the final game, hitting a forehand winner down the line on the last point, then dropped his racket and flopped on his back.
"I still can't believe it. I was playing great, and he was playing great, too," Nishikori said during an on-court TV interview. "Biggest win for me."
That's for sure: Nishikori only had one other career victory over a top-20 player. And in Ferrer, he was facing the man who eliminated Rafael Nadal at last year's U.S. Open.
Only one other man from Japan reached the fourth round at any Grand Slam tournament in the Open era: Shuzo Matsuoka was a Wimbledon quarterfinalist in 1995.
Nishikori, 18, also is the youngest man to get this far at the U.S. Open since Marat Safin in 1998. He is playing in only his second career major tournament and knocked off No. 29 Juan Monaco in the first round.
Meanwhile, American Sam Querrey, at 20, is also young and eager, saying he is "looking forward" to facing No. 1 Nadal, after upsetting No. 14 Ivo Karlovic 7-6 (7-5), 7-6 (7-5), 6-2.
It's Querrey's first berth in the fourth round of a major championship. He's already faced Nadal once, losing in three sets on a hard court in 2006.
"Won the first set, I remember, so that was cool," said Querrey, now ranked 55th. "Like, the main thing from that match I remember — I was playing at 2 (p.m.), and I knew ESPN went on the air at 3. I wanted to make it to 3 to get some ESPN time, which I did. … Hopefully I've gotten a lot better since then. He has, too."
Nadal's assessment was similar. "I managed to catch a bit of his match," said Nadal, who won for the 41st time in his last 42 matches by brushing aside Viktor Troicki 6-4, 6-3, 6-0. "He has improved a lot, and he has that powerful serve."
At 6 feet 6, Querrey is one of the few men who comes close to seeing eye-to-eye with the 6-10 Karlovic. That height and accompanying wingspan allow Querrey both to generate torque on his serves — he hit 20 aces, only four fewer than his opponent — and to handle Karlovic's own high-bouncing offerings effectively.
In other matches, No. 6 Andy Murray of Britain came all the way back from a two-set deficit to defeat a fading Jurgen Melzer of Austria 6-7 (5-7), 4-6, 7-6 (7-5), 6-1, 6-4. Tampa residents James Blake and Mardy Fish played a late match.
There were no major upsets in women's play, although No. 6 Dinara Safina had to overcome a big deficit before getting past 60th-ranked Timea Bacsinszky of Switzerland 3-6, 7-5, 6-2.
Both Williams sisters — the only two past champions left in the field — won 6-2, 6-1 against seeded foes who, in theory at least, should have provided something more of a challenge.
No. 7 Venus Williams compiled a remarkable 32-4 edge in winners against No. 27 Alona Bondarenko of Ukraine. No. 4 Serena Williams — one of five women with a shot at moving up to No. 1 by tournament's end — was never troubled by No. 30 Ai Sugiyama of Japan.
One Williams or the other has won the tournament every year from 1999 to 2002, but neither has made so much as a final since. Less than two months after playing in the Wimbledon final, won by Venus, they could square off in the quarterfinals here.
"I've had over a week to think about it," Serena said. "So right now, I'm just hoping to win my next match."
Late Friday: Andy Roddick smashed his racket not once but twice, leaving it a mangled mess that matched the state of his game at that point. Facing a big deficit, the American suddenly changed everything against a younger, less accomplished version of himself.
Roddick, the 2003 champion, used a seven-game run after trailing by a set and a break to beat unseeded and 40th-ranked Ernests Gulbis, 20, of Latvia 3-6, 7-5, 6-2, 7-5 in a second-round match that finished after 1:30 a.m. Saturday.
"He was definitely outplaying me for the first two sets. I felt like a little kid out here playing against him," Roddick said. "And then the clock struck 12, and I started playing, well, as a 26-year-old."