WIMBLEDON, England — As Ivo Karlovic unfurled his 6-foot-10 frame and pounded ace after ace after ace at Wimbledon today, his opponent quickly came to a realization.

"You cannot do nothing," said ninth-seeded Jo-Wilfried Tsonga of France.

No, you can't. Not when Karlovic, the tallest player in tour history, is at his serve-smacking best.

Karlovic hit 46 aces and never faced a single break point through four tight sets, eventually putting together a 7-6 (5), 6-7 (5), 7-5, 7-6 (5) victory over Tsonga to reach the fourth round at a Grand Slam tournament for the first time since 2004.

"What I can say?" said Tsonga, the 2008 Australian Open runner-up. "He served well, and that's it."

Told what happened, five-time Wimbledon champion Roger Federer was not particularly surprised — or impressed.

"No disrespect to Karlovic, but that is not really a tennis match. Just a stroke of luck or bad calls at the bad time — and what can you do? I lost to him too last year," said Federer, who could meet Karlovic in the quarterfinals. "Once you get to the tiebreaker, he knows it and we know it: It is 50-50.

"I think he is a good draw for players who are less highly ranked, and he is a bad draw for those who are stronger, because I have the impression that he manages to up the level of his serve against us."

Does the 22nd-seeded Karlovic mind when people criticize him for having a tremendous serve and little else to his game?

"Actually, I mean, I like it," the Croatian said with a smile, "because if I can win with only one shot, I'm, I don't know, a genius."

Karlovic topped the men's tour in aces in 2007 and 2008 and is leading in that category this season, too.

A high ace count is not always enough to win a tennis match, of course, and Karlovic arrived at the All England Club with only a 14-13 record in 2009. His modern-era record of 55 aces came in a loss to Lleyton Hewitt at the French Open last month.

It was against Hewitt that Karlovic had the signature victory of his career, on Centre Court at Wimbledon back in 2003. Hewitt was the reigning Wimbledon champion and seeded No. 1; Karlovic was ranked 203rd and making his Grand Slam debut after having failed to qualify for 10 previous major tournaments.

That upset still stands as the only time in the 41-year Open era — and one of two times since Wimbledon began in 1877 — that the defending champion lost in the first round at the All England Club.

As Hewitt said that day: "Anyone's going to have a problem trying to get back those serves all the time."

But Karlovic's career never quite took off. He did reach Wimbledon's third round that year, and the fourth round the next, but then lost in the first round at the grass-court major from 2005 to 2008.

He'll face No. 7 Fernando Verdasco on Monday for a quarterfinal berth.

Karlovic will hope to frustrate Verdasco the way he did Tsonga.

"Yeah. I was watching him little bit," Karlovic said. "Whole match, he didn't have one break point, so, of course, he was not happy about that."

Karlovic had to deal with 26 aces from Tsonga and only earned two break points. But Karlovic converted one of those, and that was enough, to go along with his success in the first- and fourth-set tiebreakers.

In the latter, Karlovic went ahead 4-1, then pushed a forehand volley long, the start of a three-point run by Tsonga. But when Tsonga put a forehand into the net, Karlovic had two match points at 6-4. Tsonga served on the first, and Karlovic sent a backhand wide.

But on the second, it was Karlovic's turn to serve. He wiped away sweat from his face with his shirt, then exhaled and bounced the ball. And then Karlovic hit — what else? — a match-ending ace, then celebrated by doing a pelvis-thrusting victory dance.

Later, Tsonga was asked whether Karlovic is the best server he's ever faced.

"Yeah," came Tsonga's simple reply. "Of course."

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AP Sports Columnist John Leicester contributed to this report.