NEW YORK -- The soggy U.S. Open limped through another rain-soaked day, completing just one match and further backing up a schedule that could stretch the tournament into next week.

After managing to squeeze just three matches in between numerous rain delays on Monday and Tuesday, organizers waited better than 13 hours before finishing another one on Wednesday -- Day 10 of America's Grand Slam.

The start of play was delayed by nearly three hours because of a stubborn mist that left courts damp and unplayable. When the weather cleared long enough for a match to begin, top-seeded Kim Clijsters won three games from No. 5 Amelie Mauresmo in 10 minutes.

Then it started raining again.

About seven hours later, two men's matches reached court. No. 4 Andy Roddick was up 6-3, 2-2 against Xavier Malisse and No. 12 Sjeng Schalken had a 5-1 jump on No. 8 Rainer Schuettler when the weather window closed and play was halted by still another rain delay. They resumed long enough for Roddick to win 6-3, 6-4, 7-6 (5). Schalken and Schuettler returned to the court but never played another point. They will resume on Thursday.

''It was tough conditions out there,'' Roddick said. ''The ball was like a watermelon. I was glad to get through it. I don't have to worry about the weather tomorrow.

''I didn't think we'd get on the court tonight. I was hanging out in a suite. Somebody said, it's not raining anymore. I'd better get downstairs.

''It's tough, frustrating. You want to get out there. You want to play.''

The tournament had ambitious plans for Wednesday, scheduling a record 106 matches in an effort to catch up. At day's end, the event was 174 matches behind where it was supposed to be with 388 matches completed at a time when it was supposed to have finished 562. There are 110 on Thursday's schedule.

The biggest problem is on the men's side of the draw where just two players, Roddick and top-seeded Andre Agassi, has reached the quarterfinals. If the Open is to conclude as scheduled on Sunday with the men's final, it would require the men still stuck in the round-of-16 to play best-of-five matches on four straight days, a grueling schedule.

''I can't imagine playing three out of five sets two days in a row, let along three or four, which is what it's looking like,'' said third-seeded Lindsay Davenport, whose quarterfinal match against No. 24 Paola Suarez was among Wednesday's postponements.

The women face an ambitious schedule of their own, with their quarterfinals scheduled for Thursday, semifinals Friday and women's final Saturday night.

''We continue to make our best effort to complete this tournament on time,'' said Arlen Kantarian, the USTA's chief executive for professional tennis. ''That challenge, of course, has gotten all the more challenging. We are determined to make the best of a very difficult situation.''

That said, Kantarian added that inclement weather on Thursday would push the entire schedule back another day, meaning the men's final would be played on Monday.

The last time the Open stretched past Sunday was 1987 when rainouts forced the final to Monday. Ivan Lendl needed 4 hours, 47 minutes to defeat Mats Wilander in four sets for the title.

Perhaps the players most disrupted by the rain this week were No. 15 Ai Sugiyama and No. 29 Francesa Schiavone.

They began their fourth-round match on Monday. It was halted in a first-set tiebreak by rain. They returned long enough on Tuesday for Sugiyama to win the tiebreak and take a 5-4 lead in the second set before the match was interrupted by rain again. They never played a point on Wednesday and so their match remains in limbo, four days after it began. The other women's fourth-round match still incomplete has No. 7 Anastasia Myskina leading Mary Pierce 7-6 (2), 2-0.

The USTA hopes to finish those matches Thursday and then move the winners immediately into the quarterfinals Thursday night, with No. 6 Jennifer Capriati to face the Sugiyama-Schiavone winner and No. 2 Justine Henin-Hardenne to play the Myskina-Pierce winner.

The other women's quarters are scheduled to begin Thursday's program with the completion of Clijsters vs. Mauresmo and Davenport against Suarez.

The Open also hopes to complete the men's round-of-16 during the day.

In the bracket whose matches started Tuesday, No. 3 Juan Carlos Ferrero leads Todd Martin 6-2, No. 11 Paradorn Srichaphan is up 4-3 against No. 6 Lleyton Hewitt, and No. 5 Guillermo Coria leads Jonas Bjorkman 6-2, 2-0.

Four other round-of-16 matches, the completion of Schuettler-Schalken and Roddick-Malisse, as well as No. 7 Carlos Moya vs. No. 22 Younes El Aynaoui and No. 2 Roger Federer vs. No. 13 David Nalbandian are also on the schedule.

If all of that falls in place, the men's quarters would be played during the day Friday with the women's semis in an added session Friday night. Then the men's semis would be played as scheduled Saturday before the prime-time women's final Saturday night and the men's final on Sunday.

That would be without any more rain on a tournament that has had more than its share.