Dressed for a night on the town, Serena Williams (searchwas all business in her first match in 4 1/2 weeks.

Williams strode into Arthur Ashe Stadium Monday wearing knee-high black boots, a denim miniskirt, a studded black tank top and dangling earrings.

After warming up, Williams had to take off the boots -- actually, they ran from the top of her black sneakers to her knees -- because U.S. Open (searchofficials told her last month that she couldn't wear them during a match.

Like Tommy Haas' sleeveless muscle shirt two years ago, the boots don't meet the "customary tennis attire" rule, tournament referee Brian Earley and tournament director Jim Curley determined.

Williams always seems to have something up her sleeve when it comes to fashion. She won the 2002 Open wearing what she called a catsuit, a skintight black outfit that caused a stir.

"It's great that Serena has so much confidence to stand out and do something different. She goes beyond tennis," 1979 and 1981 U.S. Open champion Tracy Austin said. "Tennis needs that. We need the Andre Agassis, the Serena Williams, the Maria Sharapovas, the Andy Roddicks that are willing to stand out and be different."

Williams, a two-time U.S. Open champion, advanced to the second round with ease, overwhelming Sandra Kleinova of the Czech Republic 6-1, 6-3 Monday night.