WIMBLEDON, England - Andy Roddick advanced to the third round at Wimbledon by beating Igor Kunitsyn 6-4, 6-2, 3-6, 6-2.

Playing on sunny Court 1, the No. 6-seeded Roddick hit 18 aces Thursday and lost serve only once. He'll next play No. 26 Jurgen Melzer.

Roddick, one of only three American men left in the tournament, was runner-up to Roger Federer at Wimbledon in 2004-05. Roddick has 65 grass-court wins, second only to Federer among active men.

“It was comfortable most of the time,” Roddick said. “I played my best set by far in the fourth set.”

He’ll next play good friend Jurgen Melzer, the Wimbledon boys champion in 1999. Roddick has won their eight previous meetings.

Out on Court 7, qualifier Jesse Levine of Boca Raton, Fla., reached the third round at a major event for the first time by beating lucky loser Pablo Cuevas 6-2, 6-1, 4-6, 4-6, 6-3.

Lleyton Hewitt, who won Wimbledon in 2002, upset No. 5-seeded Juan Martin del Potro 6-3, 7-5, 7-5. Hewitt broke an 11-match losing streak against top-five players.

Andy Murray defeated Ernests Gulbis in straight sets. Murray saved two break points early in the first set but never faced another against the Latvian, winning 6-2, 7-5, 6-3 in front of a packed Centre Court on Thursday. He hit 36 winners with just five unforced errors.

Murray is trying to become the first Briton since Fred Perry in 1936 to win the grass-court Grand Slam tournament.

Fabrice Santoro was eliminated from his 14th and last Wimbledon, losing in four sets to Juan Carlos Ferrero in the second round. Santoro saved 10 of 11 break points in the first set but faded to lose 6-7 (1), 6-3, 6-4, 6-3.

The 36-year-old Frenchman was playing in his record 68th Grand Slam tournament and 44th consecutive major, but has said he is retiring at the end of the year.

Hewitt's once was ranked No. 1, and he won the 2001 U.S. Open in addition to his Wimbledon title. But Hewitt dropped out of the top 100 in February for the first time in a decade, after having hip surgery in August. He’s currently ranked 56th.

“Kind of the underdog out there, a little bit,” he said.

Hewitt is now 28, married and a father. Good as he looked against the 20-year-old del Potro — a rising star who was a quarterfinalist at the Australian Open in January and a semifinalist at the French Open this month — Hewitt acknowledges it all comes a bit tougher nowadays.

“It seems like you’ve got to ice a lot more spots on your body these days than I had to eight, 10 years ago,” he said with a smile.

There were no issues with his hip or anything else against del Potro, the highest-seeded man to lose so far at Wimbledon.

Hewitt compiled 43 winners and only 14 unforced errors. He hit 14 aces and saved all seven break points he faced through the first two sets.

Then, serving for the match at 5-4 in the third, Hewitt faced an eighth break point — and del Potro managed to convert it.

“I had to sort of put it behind me,” Hewitt said. “It’s not an easy thing to do, but I’m bloody glad I did it.”

He certainly did, breaking del Potro right back to go up 6-5, then serving out the match on his second attempt.

When del Potro pushed a service return long, Hewitt dropped to his knees near the baseline. When he rose, he acknowledged a raucous group of Australians cheering for him in their yellow-and-green T-shirts and hats. Hewitt is the only man from his country who entered Wimbledon, the lowest representation for Australia at a Grand Slam tournament in the 41-year Open era.

“I heard there was a few of them sleeping over last night to get some tickets out here to come in today. I appreciate the crowd,” Hewitt said. “I love playing in London. I love playing in England. It’s a lot of fun for me. It feels like a second home, really.”

Del Potro, meanwhile, simply found it fascinating to be across the net from Hewitt for the first time during a tour-level match.

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He was struck by hearing Hewitt’s trademark shouts of “Come on!” up close and in person.

“You know, he’s one of my idols,” said del Potro, who has lost in the second round every time he’s played at the All England Club, including against Roger Federer in 2007. “I start to follow him when I was young, like 11.”

All these years later, Hewitt is still around.

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