Roddick was leading 6-7 (3), 6-4, 6-2, 2-1 when the third-seeded Djokovic quit, maintaining Roddick’s streak of semifinal appearances at Melbourne Park every alternate year since 2003.
Djokovic had just had his serve broken to go down 2-1 in the fourth set when he went to the side of the court and told umpire Carlos Ramos he could not continue.
He shook hands with Roddick and left Rod Laver Arena with the trainers.
The outside temperature with the roof open at Rod Laver Arena during the match was as high as 95.
He’d had a medical timeout after recovering a break to lead 2-1 in the third set and complained of heat-related problems.
Roddick, the 2003 U.S. Open champion, won the next five games to finish off the third set, winning the last 11 points.
Djokovic, who beat Roddick in the quarterfinals at last year’s U.S. Open, finally held the opening game of the fourth set after nine minutes but was visibly slowing down and irritated.
“To be honest I didn’t know (he was sick) until he called for help there. That’s disappointing,” Roddick said. “I feel bad for Novak right now.
“He worked so hard for this last year. To not get a fair chance to defend his title, that’s too bad.”
Roddick had only lost two points in five service games in the second set and, growing up in Florida, there was no question of his stamina. As Djokovic wilted in the heat, draping towels packed with ice around his neck during changeovers, and lingering in the shade behind the baselines as long as possible, Roddick ran to the side of the court.
“It was really difficult, conditions were extreme,” Djokovic said.
The 21-year-old Serb said he’d requested a night match because his fourth-round win over 2006 runner-up Marcos Baghdatis didn’t end until 2:26 a.m. Monday and he didn’t get to sleep until 6 a.m., so he was unable to practice.
Djokovic beat Roger Federer in the 2008 semifinals and collected his first major title by beating France’s Jo-Wilfried Tsonga in the final.
That was the only title in the last 15 Grand Slams not won by either Federer or top-ranked Rafael Nadal.
ALSO ON THIS STORY
Discuss: Sound off on tennis at Newsvine.comDjokovic went out in the semifinals at the French and U.S. Opens and the second round at Wimbledon. He finished the year off by winning the season-ending Masters Cup.
The 21-year-old Serb has a history of retiring in big matches at majors. He failed to finish his quarterfinal against Nadal at the 2006 French Open and his semifinal against the Spaniard at Wimbledon in 2007.
Roddick will next play either No. 2 Roger Federer or No. 8 Juan Martin del Potro, who were to meet in a night match.
Federer is seeking a record-tying 14th Grand Slam singles title.
Djokovic was the fourth player in two days to retire from a big singles match at Melbourne Park.
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Roddick, heat too much for Djokovic
Roddick, Aussie heat are too much for Djokovic
