NEW YORK, Sept. 8 (Xinhua) -- World No. 1 Novak Djokovic became the first man into the semifinals of the US Open on Thursday as his compatriot Janko Tipsarevic retired.
Tipsarevic knows Djokovic's game extremely well and came out swinging from the hip. He hit some mighty blows on both wings and had the season's star player utterly baffled at times. The first two sets were a scrap, but Djokovic took command in the third set and overcame a foot problem in the fourth set to take control at 7-6 (2), 6-7 (3), 6-0, 3-0 when Tipsarevic retired.
In earlier matches, defending champion Rafael Nadal and No. 4 seed Andy Murray raced into the last eight as the tournament finally resumed after two days of rain.
American veteran Andy Roddick had to have his playing court moved from the Grandstand to Court 13 for claiming the wet conditions risked his health.
Soon after Roddick's match with Spain's David Ferrer resumed water began to emerge from a crack near the baseline and the American refused to continue.
Officials used towels, duct tape and even a hoover to deal with underlying water and the players returned. But Roddick stormed off court moments later saying it was still too wet to play.
The lesser-fancied Tipsarevic surged out of the traps and raced into a 3-0 lead and had chances for a double break, but failed to take them and a brilliant forehand in the following game enabled Djokovic to get the set back on serve.
Djokovic broke again, but rather than race through the set he surrendered a 5-2 lead. Tipsarevic saved a set point at 5-4 when finding the baseline with a forehand and drew level at 5-5. Tipsarevic continued his brutal assault and secured a break for 6-5, only to produce his worst game of the set to allow Djokovic to force a tiebreak, which the world No. 1 thoroughly dominated.
The second set followed the same path as the first, with Tipsaervic forcing Djokovic behind the baseline with some wonderful hitting that drew gasps from the crowd.
The second-set breaker was far more even and it was Djokovic who blinked first when pulling a forehand into the tramline. Tipsarevic did not pass up the opportunity and levelled the match when Djokovic threw a forehand over the baseline.
Djokovic raced through the third set to love and then sapped the final bit of spirit out of his opponent with an amazing get of a drop volley in the first game of the fourth set.
Djokovic called for the trainer to attend to a blister, but it was Tipsaervic who was the beaten man physically as he had run himself to a standstill and offered his hand when 3-0 down in the fourth set.
Nadal resumed the match 3-0 down in the opening set from Wednesday, but after clinching it on a tiebreaker, the Spaniard made light work of the next two, dismissing Luxembourg's Giles Muller 7-6, 6-1, 6-2.
"It was a tough day yesterday for the players and the fans who waited many hours. Sorry about that, but thanks for still being here," Nadal said.
"After the last two days, I am happy to be through. I played well against a very tough player. The situation yesterday was not easy for us and the organizers. They tried their best but they were wrong. Everyone makes mistakes."
Next up for the world No. 2 wil be Andy Roddick as the American beat 5th seed David Ferrer of Spain 6-3, 6-4, 3-6, 6-3.
World No. 4 Murray, from Britain, raced to victory over American wild
card Donald Young 6-2, 6-3, 6-3 and will face John Isner, from United States, who beat 12th seed Gilles Simon of France, 7-6 (2), 3-6, 7-6 (2), 7-6 (4).