World number three Andy Roddick [Images] advanced to the final of the invitational Kooyong Classic after Nicolas Kiefer withdrew just four minutes into their match on Friday with an ankle injury.

Kiefer held a 1-0 lead in the first set but rolled his ankle when stopping mid-stride after Roddick had served a fault.

He sat down immediately and received treatment but decided after about 10 minutes to default to the American.

World number one Roger Federer [Images], who had to rush from his hotel after Kiefer's injury for an earlier-than-expected appearance, completed his preparations for the Australian Open with a 6-7, 6-4, 7-6 victory over Belarussian Max Mirnyi.

The Swiss, who had said he would treat Friday's game at the tournament as a competitive match, was surprisingly held to serve in the first set before Mirnyi easily won the tie break.

"It's always difficult to play against him because it's maximum, two or three shot rally and sometimes you play the right shots and he picks the right side," Federer told reporters of the world number 33.

"It's very difficult to play players like him who have a great serve and are great athletes.

The loss of the first set fired up Federer, who broke Mirnyi twice on his way to taking the second set.

The third went to another tie-break, where Federer lifted his game to stroll to a 6-0 lead before Mirnyi got his sole point in the tie break. Federer closed out the match on the next point when Mirnyi's backhand sailed over the baseline.

"I was happy I played the decent breaker in the end," he said.

"It was good to finish off, but if I'd lost it wouldn't have changed much. I played some good tennis and stayed tough."

OPEN PREPARATIONS

Roddick, who has been drawn against a qualifier in the first round of next week's Australian Open, said Kiefer's withdrawal was not the ideal preparation for him.

"Selfishly you want to play that match just to get some form," said Roddick.

"But the good news is I have another one tomorrow so I'm going to go over and try and get some practice at Melbourne Park."

Roddick will meet Tommy Haas on Saturday in the final of the eight-man invitational Kooyong tournament, which is a traditional warm up for the year's first Grand Slam.

"You want to play guys who are playing well going into the Open and obviously Tommy has played great this week," Roddick added.

"Win or lose is fine, I want to get out there and hit some shots in a match-type atmosphere, which is good.

"I feel like I'm in pretty good shape and it would be nice to get out there and just play a couple of sets."

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