NEW YORK, AUG. 27 -- Rain delays, a hail deluge and hot dog wrappers wafting across the courts were a few of the disturbances today at the U.S. Open, the tournament that makes the unusual seem typical. To hope to win it you must try to rise above it, which defending champions Boris Becker and Steffi Graf did with straight-set victories in their opening-round matches.

Graf endured two rain interruptions, including lightning bolts from swirling black clouds in the distance and a wind that blew her sideways as she headed to the locker room. But she defeated 19-year-old qualifer Maureen Drake of Canada, 6-1, 6-1, at the National Tennis Center in Flushing Meadow, the delays twice as long as the 41-minute match.

Becker had to wait out the weather and then trailed unseeded clay-court specialist Juan Aguilera of Spain by 3-5 in the first set before he went on to victory, 7-5, 6-3, 6-2.

"I thought I'd better get going," Becker said.

That was true of most of the seeded players, who started sluggishly in the oppressive humidity.

No. 8 Brad Gilbert had a menacing draw in 1988 Open champion Mats Wilander, the unseeded Swede who has been largely inactive this season as he plunged to No. 59. It hardly seemed right to call the former No. 1 player in the world an underdog, and he did not play like one, extending Gilbert for 3 hours 4 minutes before the seeded player won, 6-4, 3-6, 6-3, 7-5.

There were no upsets, but the afternoon and evening were halting and nothing seemed easy. Twenty-five matches were left unfinished, six of them suspended and 19 postponed. Gilbert and Wilander left the court at 12:15 Tuesday morning, ending an interminable day after 13 hours.

Only Monica Seles, the 16-year-old from Yugoslavia ranked and seeded No. 3, was efficient. With clear skies over the Louis Armstrong Stadium court, she swept Elena Pampoulova of Bulgaria out in the tournament's first match in 44 minutes, 6-0, 6-0.

Becker, the three-time Wimbledon champion, finally seemed to establish himself as a broader, potentially dominant player with his Open title last year. But he has failed to follow it up this season -- with no Grand Slam title as yet, shut out of the Australian and French opens and Wimbledon, and with a 43-10 record coming into the tournament. Aguilera inflicted one of those losses in May, a straight-set final on clay in the German Open, and thus was regarded as a potential upsetter, ranked No. 19.

"That makes it a little bit more difficult to step out there," Becker said.

Becker had obvious difficulty grooving his strokes in the heavy, damp air. He said he brought 11 shirts in his courtside bag, "and it was just enough."

But early sluggishness is not unusual for the muscular West German, who tends to start slowly and build his form. That habit makes him vulnerable in early rounds, and only after the uncertain first set, dropping his serve three times and committing 16 of his 28 unforced errors, did he begin to exert his usual power.

Aguilera broke him just once more for the remainder, as Becker gradually amassed 32 punishing winners.

"It was difficult after the long rain," Becker said. "It was very humid and that makes it slower. The balls got much bigger."

Becker yielded his serve to trail by 3-5 on a typical unforced error. With the open court before him across the net, he chose hesitantly to go down the line with a forehand volley, and pushed it wide. But Becker suddenly went into motion, pressing at the net to force the harried Aguilera into a series of mistakes and break serve twice consecutively for a 6-5 lead. He then recovered from a 15-40 deficit to hold serve for the set with a service winner that clattered off the Spaniard's racket.

Becker sauntered out of the stadium more assured than when he arrived.

"It feels like a home court to me now," he said.

Observers were disconcerted by the silence with which Seles advanced. Not only were there no planes roaring overhead, rerouted from LaGuardia's Runway 13, but Seles did not emit her usual high-pitched shrieks. She has been criticized for those piercing noises when she hits the ball, and has made a concerted effort to cure herself of it.

"The tennis was quiet," she said.

It was perhaps significant that Seles won so convincingly even as she admitted that she did not use the full range of her game. Her 18 winners and Pampoulova's 20 unforced errors summed up the lopsided score.

Against Graf, Drake's sole noteworthy contribution to their match was a plaid skirt that bore more resemblance to field hockey garb than tennis wear.

She double-faulted seven times, so overwrought was she against the No. 1 player in the world.

Graf wasn't particularly gratified by her performance, but attributed it partly to a lack of interest in Drake, an amateur. But perhaps it also had something to do with the rise of Seles, possessor of seven tournament titles, including her French Open victory over Graf, and some nagging health problems that have put the West German on the defensive this season.

The Open is regarded as her chance to reassert herself, but she acknowledged that the state of her game is not what she would like it to be, set back by a minor operation to clear a painful sinus condition. Inconsistency was evident in a three-set final with 14-year-old Jennifer Capriati at a tuneup event in Mahwah, N.J., on Sunday, and again today.

Two national capital area products were dismissed in straight sets.

Dan Goldie, former resident of McLean, Va., was a 6-1, 7-5, 6-1 casualty of an unfortunate draw against Potomac, Md.-born, 12th-seeded Pete Sampras. Stacey Martin of Largo, Md., ranked No. 103, was upset by Miriam Oremans of the Netherlands, 6-3, 3-6, 6-2.

No. 14 Jim Courier dropped the third set with Wally Masur of Australia but was relieved to otherwise routinely defeat an upset-minded player who had won their last meeting, 6-4, 6-0, 5-7, 6-1.

The unseeded Wilander had taken an eight-month sabbatical from tennis, in part because of the death of his father. This was his third straight first-round loss, and his earliest elimination from the Open. The idleness told heavily on Wilander in the taut match. He was alternately brilliant and error-prone, as he lost a 5-2 lead and two set points in the fourth set.

"It's the best match I've played since I started playing again," he said. "But I still lost. The problem is I play some loose points now and then, and I can't really afford that."

Tim Mayotte was not seeded, and that estimation of the former Wimbledon and Australian Open semifinalist, and last year's quarterfinalist here, proved accurate. The veteran once ranked No. 10 but currently just No. 26 was defeated by Thierry Champion of France, 7-5, 3-6, 6-3, 7-5.

Mayotte's problems are a nagging injury to his right knee, a change of coaches, and perhaps his 30 years. The loss raised the spectre of retirement.

"There are a lot of reasons. It's complicated," Mayotte said.

"I just have to go back and reassess where I am. I just have to keep working at it, or stop. I'll try to go back once more and give it another year."