NEW YORK -- A sweat-soaked Pete Sampras seemed to barely be able to muster the strength to wave to the crowd after his victory. Two hours earlier, on another court, Andy Roddick packed a match's worth of athleticism and emotion into just one sequence.

	Pete Sampras took a two-set lead en route to a four-set victory over Tommy Haas.

Sampras and Roddick, at opposite ends of their careers, both won Tuesday night to set up a showdown in the U.S. Open quarterfinals.

The 31-year-old Sampras powered 27 aces, was aided by his opponent's late double faults and got past third-seeded Tommy Haas 7-5, 6-4, 6-7 (5), 7-5. It was Sampras' 200th Grand Slam tournament match victory.

''It was a long night. I was feeling it a little bit at the end. It's prety humid out here,'' said Sampras, without a title since July 2000. ''They're big matches, especially the year that I've had. It's been a little bit frustrating, but I've still got the game.''

Playing on a heavily taped bruised left foot, the 11th-seeded Roddick reached the Open's final eight for the second straight year with a 5-7, 6-4, 6-4, 6-4 victory over No. 26 Juan Ignacio Chela of Argentina.

''It's kind of the generations overlapping,'' said Roddick, who turned 20 Friday. ''I grew up idolizing him. I have a great deal of respect for Pete and what he's done. Having said that, I want to go out there and play some ball.''

For better or worse, Roddick was the picture of youthful exuberance against Chela.

At 3-3 in the second set, the American produced the point and midmatch celebration of the tournament.

U.S. Open glance

WEATHER: Sunny and warm with a high of 82. ATTENDANCE: Day session: 22,542. Night session: 19,153. WINNERS: Men, Fourth Round: No. 11 Andy Roddick, No. 17 Pete Sampras, No. 24 Sjeng Schalken, No. 28 Fernando Gonzalez. Women, Fourth Round: No. 2 Venus Williams, No. 6 Monica Seles. Quarterfinals: No. 1 Serena Williams, No. 4 Lindsay Davenport. LOSERS: Men, Fourth Round: No. 3 Tommy Haas, No. 26 Juan Ignacio Chela, Arnaud Clement, Gustavo Kuerten. Women, Fourth Round: No. 9 Martina Hingis, No. 14 Chanda Rubin. Quarterfinals: No. 11 Daniela Hantuchova, Elena Bovina. STAT OF THE DAY: The second set of the Venus Williams-Chanda Rubin match, won by Rubin 6-4, was the first set lost by any of the top four seeded women. QUOTE OF THE DAY: "I got up at 10:30 because at 11 the breakfast is closed, otherwise I would stay in bed longer.'' -- Sjeng Schalken after being asked what time he got to bed Monday night -- 2:30 a.m. -- and what time he got up.

Roddick ran -- well, hobbled -- all the way from baseline to net to get to a drop shot, then switched directions to race to the baseline for a lob and, with his back to the net, barely flicked the ball over the net. The point wasn't over. Next came two volleys by Chela, the second of which Roddick got to and smacked a backhand winner down the line. Still moving, Roddick dropped his racket, raised his arms in a V, climbed past a sign to get to the stands, and slapped high-fives with spectators.

''I hit the shot and all I heard were these people going crazy, and I just went over,'' Roddick said. ''I think it helped turn things around. That was just totally spontaneous. There's not really an explanation for it.''

Later, he dived for a shot during a rally, leaving a blotch of sweat along the baseline. Fans watching Sampras' fourth-round match in Arthur Ashe Stadium were shown a replay of that effort on the big scoreboards and roared their approval.

Roddick's volatility also came out in an obscenity-laced tirade at the chair umpire after Chela finished the fifth game of the fourth set with an ace.

''You know it was out!'' was the cleanest thing Roddick yelled while arguing, before shouting, ''Stop! Stop! Stop!'' and waving a hand as the umpire tried to speak.

It brought to mind Roddick's rant in the final game of his five-set loss to Lleyton Hewitt in the 2001 Open quarterfinals. Roddick hit a forehand that a linesman called good, but the chair umpire overruled, even though the ball landed on the far sideline.

''It was straight on the line!'' Roddick screamed then. ''How can you overrule the far side of the court? What is wrong with you? You can't overrule it at 4-5 in the fifth set. What are you? Are you an absolute moron?''

Against Chela, Roddick dug himself a hole by double-faulting to lose the first set.

He immediately asked for a medical timeout, and ATP Tour trainer Doug Spreen taped a pad to the outside of Roddick's left foot to fight swelling.

''My foot was hurting, but adrenaline is definitely an amazing thing,'' Roddick said.

The winner of Sampras-Roddick will play No. 24 Sjeng Schalken of Netherlands or No. 28 Fernando Gonzalez of Chile. Like Roddick, neither has been to a major semifinal.

Schalken beat Gustavo Kuerten, a three-time French Open champion, 6-3, 7-6 (6), 6-7 (5), 7-6, while Gonzalez defeated Arnaud Clement 6-4, 6-2, 6-3.

On the women's side, Serena Williams, trying to become the first woman since Steffi Graf in 1996 to win three majors in a season, and Lindsay Davenport won to set up a semifinal meeting. Williams' sister Venus and Monica Seles will meet in a quarterfinal on the other side of the draw after picking up victories early Tuesday.

In a match that ended shortly before midnight, Sampras tripped over his own feet during the third-set tiebreaker against Haas and fell to the court.

But his game wasn't really affected.

He kept ripping untouchable serves, wound up with 82 winners to Haas' 36, and held steady in the fourth set until the German came undone. Serving to stay in the match, Haas double faulted to 15-30, watched as Sampras had a forehand winner followed by a backhand volley winner, then double faulted again to end it.

After Sampras beat Greg Rusedski on Monday night, Rusedski said: ''He's a step and a half slow coming into the net. He's just not the same player. I lost the match. He didn't win the match tonight. He's not playing that great. I'll be surprised if he wins his next match, to be honest with you.''

Asked to respond Tuesday, Sampras smiled.

''I don't really worry about what he says,'' Sampras said. ''Against him, I don't really need to be a step and a half quicker.''