Last eight beckons for Djokovic after Wawrinka injury

The pair had begun their fourth-round clash on Tuesday night before rain brought a premature end to play and they were on and off the court again before the match finally resumed just after 1pm (US time) yesterday.

Djokovic was tested in the first set but after that it was a one-sided contest and Wawrinka called it a day with the second seed leading 6-4 6-1 3-1, although the reason was not immediately apparent.

They managed only two games before the rain came on Tuesday, Djokovic winning both of them, but Wawrinka quickly retrieved the break on the resumption.

The last time the Swiss beat Djokovic was six years ago and his cause was not helped when he promptly dropped his serve again.

Djokovic has cruised through the draw in New York, but he was making more unforced errors than usual on a sparsely-populated Louis Armstrong Stadium and was unable to serve out the set.

However, for the second time Wawrinka failed to hold serve straight after breaking and things swiftly went downhill in the second set for the 18th seed.

After saving a break point in the opening game, Djokovic reeled off four games in a row, and Wawrinka responded by smashing his racquet on the court. It did not help, though, and he was quickly a break down in the third set.

Wawrinka talked to the trainer after the change of ends and, following the fourth game, he called Djokovic to the net and shook hands.

In the women’s draw, Maria Sharapova maintained her remarkable record in deciding sets to defeat Marion Bartoli and reach the semi-finals for the first time since winning the title six years ago.

Not since her third-round loss to Flavia Pennetta here 12 months ago has Sharapova lost a three-set match, winning 12 out of 12 this season.

She was pushed to the limit by Bartoli, who had led 4-0 when rain forced the match to be postponed yesterday, but eventually came through 3-6 6-3 6-4 to set up a meeting with world No 1 Victoria Azarenka.

Sara Errani continued her remarkable season by beating best friend and doubles partner Roberta Vinci to reach the semi-finals, winning 6-2 6-4.

n Rafael Nadal will not need surgery and could be back on the practice court in a month’s time, according to his doctor.

The world No 3 has a partially torn patella tendon in his left knee, which has already caused him to miss the Olympics and the US Open, but Dr Angel Ruiz Cotorro said: “The tendon is responding well to treatment. In one month, if the tests are positive, he can resume training.”