NEW YORK — NEW YORK -- Call it U.S. Open warfare. Or call it whining by some of the world's richest athletes. In what has become as traditional to this tournament as strawberries and cream are to Wimbledon, the players are trashing the place again. Verbally, that is. It's not just young foreigners such as Andrei Medvedev who are not used to the clamor of New York and the clutter of the National Tennis Center. Many Open veterans, including some former champions, are taking their shots as well. "It's probably the most difficult to win of all four [Grand Slam events] because of different circumstances," Boris Becker, who won here in 1991, said yesterday after dispatching Sergio Cortes of Chile, 6-4, 6-4, 6-3 in a fourth-round match. "You have the crowd here. You have heat here. You have noise here. At the other three, you don't have that much." Said former four-time women's champion Martina Navratilova: "This is a rough tournament. There is nothing really pleasant about it except when you are out there playing the match. That is the great part. But it is really the only part, because the rest is a struggle. You can't enjoy it, but we didn't come here to sit by the tennis pool and catch some sun." Everything has come under attack, from the overcrowded conditions of the players' lounge to the overused practice courts to the overabundance of spectators. The players don't seem to care that plans are under way to refurbish the 15-year-old complex. Asked what he liked about the Open compared with the other Grand Slam tournaments, Medvedev said, "Drinks are for free. It is very nice. Massage for free. Transportation free. "Beside [that], it is a very complicated tournament. Because it is a Grand Slam, because you are trying to concentrate every match and because the conditions -- [it's] hard to play and the facility needs to be improved." Then there's the matter of the practice courts. Top-seed Jim Courier said there were "potholes" on some of them. Others have complained about the practice courts being a different speed from the show courts and that the Grandstand Court -- which has been the scene of several upsets, including that of two-time defending champion Stefan Edberg in the second round last week -- is noticeably slower than the Stadium Court. Joked Navratilova, "As long as they don't put speed bumps on the court, I don't mind." It was left to Navratilova, who has played in more Opens than anyone here, to put things in the proper perspective. Asked if her peers were complaining a little too much, Navratilova smiled. "Yeah, I think we are getting paid very well to suffer a little bit," she said. Surprise, surprise Maria Jose Gaidano is not complaining about anything these days. After losing in the qualifying tournament for the Open, the 20-year-old from Argentina became a "lucky loser" when Mary Joe Fernandez pulled out before her first-round match with abdominal pains. The lucky loser has since become a surprise winner. Ranked 137th, Gaidano won her third straight match Saturday night with a 2-6, 6-2, 6-3 victory over Jenny Byrne of Australia. Gaidano will meet Natalia Zvereva in a fourth-round match today. Over and out Mats Wilander's memorable return to the Open ended yesterday, with a 6-4, 6-4, 6-4 third-round loss to No. 15 Cedric Pioline of France. Wilander seemed to have little left after going -- five sets and playing until past 2 a.m. Saturday morning. "I don't remember feeling as helpless out there," Wilander said. Courier advances In the featured match last night, top-seeded Jim Courier fell behind MaliVai Washington 4-2 in the first set, but came back to win easily, 6-4, 6-4, 6-2, on the Stadium Court. The victory advances Courier to the fourth round. Date with destiny? Kimiko Date yesterday became the first Japanese player to make it through to Open quarterfinals in 18 years by upsetting No. 8 seed Jana Novotna, 6-4, 6-4. Date (pronounced DOT-ee) had previously beaten No. 9 seed Anke Huber. FEATURE MATCHES Matches today on the show courts and others involving seeded players in the U.S. Open: STADIUM COURT Day session Michael Chang (7), Henderson, Nev., vs. Wayne Ferreira, South Africa; Thomas Enqvist, Sweden, vs. Pete Sampras (2), Tampa, Fla.; Martina Navratilova (3), Aspen, Colo., vs. Helena Sukova (12), Czech Republic. Night session Brad Gilbert, San Rafael, Calif., vs. Thomas Muster (12), Australia; Jonas Bjorkman, Sweden, and Patrick Rafter, Australia, Ken Flach, Alpharetta, Ga., and Rick Leach, Laguna Beach, Calif. (12). GRANDSTAND COURT Day session Maria Jose Gaidano, Argentina, vs. Natalia Zvereva, Belarus; Arantxa Sanchez Vicario (2), Spain, vs. Nathalie Tauziat (14), France; Alexander Volkov (14), Russia, vs. Chuck Adams, Pacific Palisades, Calif.