TENNIS/AUSTRALIAN OPEN:ANDY RODDICK has more reasons than most, 15 of them to be precise, to rue the career of Roger Federer. The two first played each other way back in 2001, and it took the American only another four matches to beat the Swiss. He may have felt he had cracked it, and that life was sweet. Little could he have comprehended that it would be another five years, and 11 successive defeats, before he won for a second time – in Miami last year.

Small wonder that Roddick is steeped in admiration for the Swiss, whom he will meet in the semi-finals in Melbourne: “I was really happy to see Roger win the US Open last year. He has nothing to prove. He’s the greatest. The guy made two finals, a semi-final, and won a slam last year and people were saying he’s off form. I think he deserves a lot more respect than that.”

Federer did not get on court until after 10pm in Melbourne yesterday, but was off it in only one hour 20 minutes, defeating Juan Martin del Potro of Argentina, the number eight seed, 6-3, 6-0, 6-0 and reeling off 13 successive winning games.

“Andy and I have had some big matches and it’s always a pleasure to play against him,” he said afterwards. “Sometimes people don’t give him enough credit.” A mutual admiration society, then, though little is shared about the outcome of their matches: 15-2 to Federer.

An upbeat Federer also felt his match against Del Potro exceeded his expectations. “Things went much better than I expected,” said the world number two. “I was really happy the way I came out and played. I kind of felt good from the start. The longer the match went, the more he struggled and the better I got.”

Roddick is currently attempting to re-invent himself under the guidance of Larry Stefanki, a one-time coach to Tim Henman. He has persuaded the former US Open champion to lose weight, which has enabled him to move more quickly.

Roddick reached the semi-finals here for a fourth time, and his ninth in all slams, when the reigning champion, Serbia’s Novak Djokovic, quit when trailing 6-7, 6-4, 6-2, 2-1. Djokovic has now retired four times in a slam since 2005, which might seem to point to a considerable flaw in his character had he not had such success.

Djokovic has been ranked number three for all but one week since July 2007, and three times has been within one win of being number two. Murray, having lost in the fourth round against Fernando Verdasco, may have to wait until the clay-court season to mount his next ranking challenge on the Serb as he looks to become the highest-ranked British male player in the open era at number three.

The last Murray standing, Jamie, having lost in the first round of the men’s doubles last week, went out in the second round of the mixed doubles when he and his partner, Liezel Huber, the fourth seeds, were beaten 6-7, 6-2, 10-4 by Andy Ram and Nathalie Dechy.

Meanwhile, Jelena Dokic insisted she had no reason to be disappointed after bowing out of the Australian Open against Dinara Safina. The Australian, who came into the grand slam tournament on a wild card, had her dream run ended by the big-hitting Russian third seed 6-4, 4-6, 6-4 in the quarter-finals.

But after battling back from depression and becoming estranged from her family, Dokic has re-ignited her tennis career and won back the hearts of her adopted country folk with her efforts. Last night’s game was just one match too far, however, as the toll of not playing at such a high level for almost three years, and a sprained ankle suffered late in her previous match, finally took its toll.

“I have really fought well this week. I have no regrets. I just would like to keep it going,” she said. “I played well with a girl who’s number three in the world today. I can still really take positives out of today, even though some of the points and the shots that I played at some stages of the match were maybe not right.

“It’s been a great start to 2009. I couldn’t have asked for anything more.

“I have to take all the positives and negatives out of today and really learn for the rest of the year about what I will do differently in a match like that. There’s absolutely nothing to be disappointed about,” she said.

In an error-strewn but gripping match, Dokic lost a tight first set but bounced back immediately in the second to break the big-hitting Russian – who served 11 double faults in the match – and take a 3-0 lead.

But Safina then held serve to love and got the break back, only to lose the following service game to go 5-2 behind.

Although she broke again in the ninth game, it was not enough and a double fault handed Dokic, who hit some sublime winners down the line, the second set.

It was more of the same in the third as the error count from both players mounted.

Dokic failed to hold serve in the opening game but pushed the Russian to four deuces in the next before Safina closed it out.

The games then went with serve until the eighth when a backhand winner from Dokic got her back on level terms at 4-4. It was short-lived, though as another lengthy game, where Dokic saved three break points, finally went the way of Safina, who then wrapped up the match when Dokic found the net.

Safina admitted it had been tough taking on Dokic and the crowd on the Rod Laver Arena.

“It was not easy to play, you know, having the whole crowd against you,” the 22-year-old said. “Because when you have the whole crowd behind you whenever you do a great shot, they pump you and then it makes you go for more and more.

“When you make a great shot and basically only my box is clapping for me, that’s tough.”