Injury fear looms large over Nadal

Rafael Nadal had hoped that his physical problems were behind him when he arrived here a fortnight ago but the Spaniard will be forced to take another break from the game once the US Open is over.

Nadal, whose hopes of completing his quarter-final against Fernando Gonzalez yesterday were dashed by rain, has been advised by doctors to rest after aggravating a stomach muscle injury he suffered last month. The world No 3 last night withdrew from Spain's Davis Cup semi-final against Israel in Murcia next week, though he plans to attend the tie as a spectator.

Toni Nadal, the Australian Open champion's coach and uncle, said that the injury had been "very, very bad" on Thursday night, when he had on-court treatment as he played the best part of two sets against Gonzalez before rain intervened. It remains to be seen whether he will return in time for the next Masters tournament in Shanghai next month.

It has been a difficult summer for Nadal, who took two months out after the French Open because of tendinitis in both his knees. He returned in the back-to-back Masters events in Montreal and Cincinnati last month and appeared to be coping with the stomach problem until it flared up again on Thursday.

Roger Federer must have been one of the only men here with a smile on his face as rain and gusting winds cut a swathe through the final weekend for the second year in succession. Federer, having already secured his place in the last four against Novak Djokovic, was able to put his feet up, while his greatest rival, Nadal, spent a frustrating day in the players' lounge waiting for the weather to improve.

Play was eventually called off at 6pm as tournament organisers prepared for a Monday – and maybe even a Tuesday – finish. The weather forecast for today is not much better, but the Nadal-Gonzalez match has been scheduled to resume at noon (5pm BST), followed by the two women's semi-finals (Serena Williams against Kim Clijsters and Yanina Wickmayer against Caroline Wozniacki). Tomorrow's provisional programme features the men's semi-finals during the day and the women's final in the evening, with the men's final pencilled in for Monday afternoon.

Nadal and Gonzalez are potentially the biggest victims of the weather and will have every reason to feel hard done by. The weather had been good enough on Thursday afternoon for Juan Martin del Potro, the third man into the last four, to complete a four-set victory over Marin Cilic, but tournament organisers chose not to stage the last quarter-final at the same time on another court, despite weather forecasts predicting rain in the evening.

Gonzalez and Nadal subsequently spent five hours trying to play their match in the night session. Nadal took the first set on a tie-break and the score was 2-2 in the second when the players were forced off court for an hour and a quarter. They returned and were playing a second set tie-break, with Gonzalez serving at 2-3, when rain halted proceedings for a second time. Two hours later, at just after midnight, play was called off for the day.

Whatever happens now, Nadal and Gonzalez know that if they reach the final they will have to play at least three days in succession. It is all reminiscent of last year, when the scheduling again favoured Federer, whose earlier start on the final Saturday meant that he was able to complete his semi-final before a tropical storm struck later in the afternoon. Nadal and Andy Murray had to return to complete their semi-final the following day, which meant that the Swiss had 24 more hours than Murray to prepare for the final, which was played on the Monday.

Nadal, who did not look happy on court on Thursday, had three set points in the 10th game of the second set. Gonzalez saved two with service winners, but Nadal appeared to be about to convert the third when the umpire halted play mid-point after a napkin blew across the court. Gonzalez won the replayed point and then took the set into a tie-break. The winner of the match will play Del Potro, who beat Cilic 4-6, 6-3, 6-2, 6-1.

With Wimbledon having built a sliding Centre Court roof and the French Open planning to install a retractable cover by 2014, the US Open will soon be the only Grand Slam tournament with no facility to play during rain. Although it would be feasible to put a roof over the smaller Louis Armstrong Stadium, the sheer size of the 23,000-capacity Arthur Ashe Stadium would make covering the main arena a massive task. The weather problem here is compounded by the fact that there are not even any covers on the courts.