Mother Nature hasn't been kind to the last grand slam of the year. On the eve of the tournament, New York was battered by Hurricane Irene and now the remnants of Tropical Storm Lee are drenching the Eastern seaboard and threatening to ruin the last grand slam of the year.

For the world's best players, the next few days could shape up as a test of their patience and a race to beat the weather as much as their power and skill.

Tuesday's entire program was canceled before a ball was hit because of showers in New York and the forecast for the rest of the week is just as bleak.

The postponement left tournament officials with a backlog of matches and forced them to reorganize Wednesday's schedule. Instead of four singles matches on the Arthur Ashe center court, there will not be 10 singles matches, spread over three courts.

Each of the 20 remaining players -- 12 men and eight women -- will be in action on the same day, providing a galaxy of stars for the tennis fans at Flushing Meadows, but raising doubts about whether all the matches will be finished in time.

For some players, the delays and interruptions are a nuisance. For others, they may come as a welcome relief.

Rafa Nadal collapsed after his last match because of severe cramps caused by the intense humidity on court. The prospects of cooler temperatures for his clash with Gilles Muller of Luxembourg would hold obvious appeal.

Nadal's match, one of four fourth-round clashes still be played, has been pushed to the front of the queue in the hope they can get them done before starting the quarter-finals.

Andy Murray and Andy Roddick, who were both originally scheduled to play on the Arthur Ashe Stadium, have had their matches moved to smaller showcourts, which are not normally used at this stage of the tournament, to try and speed them up.

Roddick plays fifth seed David Ferrer of Spain at Louis Armstrong Stadium while Murray tackles American wildcard Donald Young on the Grandstand Court.

All four women's quarter-finals have been added to the schedule. Williams plays Anastasia Pavlyuchenkova in the night session while world number one Caroline Wozniacki is due to meet Andrea Petkovic.

The first two men's quarters have also been added, with world number one Novak Djokovic locking horns with his Serbian Davis Cup team mate and Federer squaring off with Jo-Wilfried Tsonga in the late match.

Look, if the rain comes, that's what it is. You can't change that, Federer said.

'We had to come back the next day several times already.

That's just a part of out game.