Andy Roddick injured, retires in second-round match vs. Lleyton Hewitt

Andy Roddick received medical treatment on his leg before withdrawing from his match against Lleyton Hewitt. (Reuters)

MELBOURNE, Australia -- On set point in the third set, Lleyton Hewitt sliced a cross-court backhand that zipped along until it hit the netcord, popped up, clipped the netcord again and dribbled over onto Andy Roddick's side of the court. That shot gave Hewitt a 3-6, 6-3, 6-4 lead, proved to be the last point of the match and summed up Roddick's luck on Thursday night, a night that began with promise and ended in disappointment.

Roddick retired from his much-anticipated match with his longtime Aussie rival after re-aggravating a right hamstring injury that he suffered while training in December. Roddick came down awkwardly after lunging for a forehand in the third game of the second set. He called the trainer on the changeover and left the court for treatment, but his movement was clearly hampered when he returned, particularly to his backhand side.

Roddick gamely played on -- "You don't really have much time for clarity in that situation," he said later --  but after dropping the next two sets, he discussed the situation with the trainer and promptly retired, sending Hewitt through to the third round to face Milos Raonic.

"If somehow you pull a rabbit out of the hat, I don't think you play in two days," a somber Roddick said. "If I'm looking at timelines, I think there's three weeks or so before I have to play again. I like those timelines a lot more than two days."

It's a frustrating result for Roddick, who, thanks to a slightly longer offseason, came here fit and hungry to fight his way back into the top 10 where he feels he belongs. To come up lame in a completely winnable early-round match was a crushing blow of bad luck that knocked him out of the tournament and leaves him racing the clock to get himself fit for the rest of the season.

It also likely squashes the chance of seeing Roddick and Serena Williams team up at the Australian Open. Roddick hadn't officially withdrawn from the mixed doubles tournament as of this writing, but the 29-year-old American told reporters that he was targeting next month's event in San Jose, Calif., for his return.

"It's frustrating. It's discouraging," Roddick said. "Your sensible mind says to have a sense of perspective. You still have it pretty good. The competitor in you feels terrible and wants to break stuff.

"I can't really complain. I had 10 years, pretty much, of a clean slate. That's a lot more than most people get. The last two years have been pretty tough. It's tough physically. It's as tough mentally, though. It's hard."

When asked whether these sorts of injuries make him think about whether he's in the late stage of his career, Roddick acknowledged that it creeps into his mind. "I don't think it's coincidental that all of a sudden in the last year and a half or two years that I'm getting hurt more," he said.

"So, yeah."

Hewitt, 30, can sympathize with Roddick as a fellow former No. 1 who has battled injuries and is looking for some late-career magic.

"Andy's a great competitor. He always has been," Hewitt said. "He's similar to me. He plays with his heart on his sleeve. He has that never-say-die attitude as well. It's never easy to play injured or to pull out of a match. It's not a good feeling."

Here's hoping that Roddick takes the time he needs to get his body back to 100 percent before taking the court again. Given the crowded schedule due to the Olympics, 2012 is not the year to be playing hurt week in and week out.