Tracy Austin

MELBOURNE, Australia - With some help from the heat, Andy Roddick ended Novak Djokovic’s chances at defending his Australian Open title. Roddick was up two sets to one and leading 2-1 when the broiling sun finished off Djokovic, who despite using ice packs and massages, became increasingly woozy and was forced to retire.

The seventh seeded Roddick has a semifinal date with second seeded Roger Federer, against whom the American has won just two of 17 matches. As much as Roddick would like to borrow a line from Vitas Gerulaitis, who said, “No one bests Vitas Gerulaitis 17 times in a row” after he finally defeated Jimmy Connors, Federer will prevail.

It was hot, so hot that the Tournament Referee, who is responsible for deciding when to close the Rod Laver Arena roof, received reports of temperature readings on a half-hour basis. When Djokovic called it quits the temperature was 37.1° Celsius (almost 99° Fahrenheit). He seemed to be dizzy and disoriented. After the match, he said he was cramping and his whole body was sore.

Given the shot-making skills of Roddick and Djokovic, it is not surprising that both players hit 43 winners. Roddick, in a solid performance, made only 14 unforced errors while his opponent made a capricious 39. At one point, Roddick was serving 73 percent on first serves. Pushed by his new coach, Larry Stefanki, Roddick lost 15 pounds in the offseason. The loss of weight made a difference as he was quicker and his backhand stronger. Roddick’s stamina was never in question.

Because Roddick is more mobile, he can play better defense and he has improved from the backcourt. He has always had the big forehand but he should play closer to the baseline. He gives up too much real estate standing eight or nine feet back. While he may be more comfortable in that position, it gives his opponent way too much time to hit the ball.

Djokovic, who looked lethargic toward the end of the second set, took an injury timeout at 1-2 in the third set. He had been eating bananas and energy bars, and icing his neck on changeovers. When the trainer came on court, he massaged Djokovic’s thighs, calves, neck and arms with some kind of cream and then ice. In the old days, that wouldn’t have been allowed. It would have been called “loss of conditioning” but they have changed the rules. It used to be that you would be defaulted if you were treated.

I am not sure how long Djokovic was worked on, but you have to remember that Roddick was sitting, then walking around, waiting anxiously to play during the delay. After the match he commented on that fact when he came back and served three doubles faults in the next game because “if you go for a 30-minute run and sit down for 12 minutes and you get up and try to run quickly, you feel terrible.”

Overall Roddick’s play has reflected the wisdom of Stefanki, who really knows the game. Another important point is that Roddick stayed calm. He played patiently and really seemed to be enjoying himself.

For Djokovic, who was 2-1 in his career against Roddick, it was his fourth retirement in Grand Slam competition. In 2007, a blister on his right hand forced him to abandon a semifinal contest against Rafael Nadal at Wimbledon.

In back-to-back years, he left Roland Garros by retiring. In 2006, a respiratory ailment sidelined him against Nadal in the quarterfinals, and in 2005, back problems sent him packing against Guillermo Coria in the second round.

Often, figures are little more than numbers. With the Serb, that’s certainly the case. Before the match with Roddick, he was 20-30 against Top 10 players in his career but he had lost only one of his last 19 matches against Americans.

Speaking of numbers, I don’t know if Roddick likes odd numbered years but he has equaled his best Australian Open performance reaching the semifinals for the fourth time. The Junior Boys’ winner in Melbourne in 2000 he has made the final four here in 2003, 2005 and 2007. He has played Federer just once in Melbourne, falling to him in straight sets in 2007.

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His last win against the Swiss came in their most recent match last year at the ATP Masters Series Miami. Comparing the two, Roddick is always thought of as a huge server but his forehand is a weapon as well. Federer’s, however, is the best in the game and he is no slouch when it comes to hitting telling returns. Just look at the way he handled Roddick’s serve in the 2005 and 2004 Wimbledon finals.

As far as the backhand, I would go with Federer’s as the stronger of the two. Against Djokovic, Roddick's backhand looked more fluid and it had a bit more penetration. I still feel his arms seem a little stiff and if that is the case, you lose a little acceleration.

Roddick has been working on his volley and his balance while hitting the shot is getting better, but I’d also favor Federer when it comes to net play. He has better feel and understands what goes into making decisive volleys.

Since both players are fit they should be able to deal with the heat. Roddick’s larger concern is figuring out a way to get past Federer and give himself a shot at his second career Grand Slam.