NEW YORK — Rafael Nadal stepped out of the players' cafeteria at the U.S. Open a little before 3 p.m. Friday and pressed his face against a window, cupping his hands around his eyes as he scanned the soaked tournament grounds.

Yep, it was still pouring.

And he, like everyone else, was still waiting.

Rain threw the U.S. Open into disarray for the second consecutive year, meaning both singles finals will be pushed back again, and the tournament will end Monday at the earliest.

"There are some unknowns here," U.S. Tennis Association spokesman Chris Widmaier said.

A mix of showers and mist forced postponement of all of Friday's three scheduled singles matches. That included six-time major champion Nadal's quarterfinal against No. 11-seeded Fernando Gonzalez, a match already suspended Thursday night because of showers after Nadal won the first set in a tiebreaker and led 3-2 in the second-set tiebreaker.

Also delayed: The two women's semifinals, one between defending champion Serena Williams and 2005 champion Kim Clijsters, the other between a pair of 19-year-olds never before this far at a Grand Slam tournament, Caroline Wozniacki and Yanina Wickmayer.

Those three matches were all rescheduled for Saturday, when the forecast again calls for rain. Saturday's new schedule was set to have Nadal-Gonzalez begin at noon, followed by Wozniacki-Wickmayer, with Williams-Clijsters slated to start after 8 p.m.

Assuming the women's semifinals can be completed Saturday, that final will be moved to Sunday. Organizers were still trying to iron out all the details, including determining where matches will be aired on TV.

If Nadal-Gonzalez finishes Saturday, the men's semifinals will be Sunday. The Nadal-Gonzalez winner meets No. 6-seeded Juan Martin del Potro, and five-time defending champion Roger Federer faces No. 4 Novak Djokovic.

The men's final then would be moved from Sunday to Monday. Last year, the U.S. Open men's final was played on a Monday for the first time since 1987.