NEW YORK (AP) - Serena Williams walked toward the line judge, screaming, cursing and shaking a ball in the official's direction, threatening to "shove it down" her throat.
On match point in the U.S. Open semifinals Saturday night, defending champion Williams was penalized a point for unsportsmanlike conduct - a bizarre, ugly finish that gave a 6-4, 7-5 upset victory to unseeded, unranked Kim Clijsters.
The match featured plenty of powerful groundstrokes and lengthy exchanges. No one will remember a single shot that was struck, though, because of the unusual, dramatic way it ended.
With Williams serving at 5-6, 15-30 in the second set, she faulted on her first serve. On the second serve, a line judge called a foot fault, making it a double-fault - a call rarely, if ever, seen at that stage of any match, let alone the semifinals of a Grand Slam tournament.
That made the score 15-40, putting Clijsters one point from victory.
Instead of stepping to the baseline to serve again, Williams went over and shouted and cursed at the line judge, pointing at her and thrusting the ball toward her.
"If I could, I would take this ... ball and shove it down your ... throat," Williams said.
She continued yelling at the line judge, and went back over, shaking her racket in the official's direction.
Asked in her postmatch news conference what she said to the line judge, Williams wouldn't say, replying, "What did I say? You didn't hear?"
"I've never been in a fight in my whole life, so I don't know why she would have felt threatened," Williams said with a smile.
The line judge went over to the chair umpire, and tournament referee Brian Earley joined in the conversation. With the crowd booing - making part of the dialogue inaudible - Williams then went over and said to the line judge: "Sorry, but there are a lot of people who've said way worse." Then the line judge said something to the chair umpire, and Williams responded, "I didn't say I would kill you. Are you serious? I didn't say that." The line judge replied by shaking her head and saying, "Yes."
Williams already had been give a code violation warning when she broke her racket after losing the first set. So the chair umpire now awarded a penalty point to Clijsters, ending the match.
"She was called for a foot fault, and a point later, she said something to a line umpire, and it was reported to the chair, and that resulted in a point penalty," Earley explained. "And it just happened that point penalty was match point. It was a code violation for unsportsmanlike conduct."
When the ruling was announced, Williams walked around the net to the other end of the court to shake hands with a stunned Clijsters, who did not appear to understand what had happened.
"I used to have a real temper, and I've gotten a lot better," Williams said later. "So I know you don't believe me, but I used to be worse. Yes, yes, indeed."
Lost in the theatrics was Clijsters' significant accomplishment: In only her third tournament back after 2 1/2 years in retirement, the 26-year-old Belgian became the first mother to reach a Grand Slam final since Evonne Goolagong Cawley won Wimbledon 1980.
"The normal feelings of winning a match weren't quite there," Clijsters said. "But I think afterwards, when everything kind of sunk in a little bit and got explained to me about what happened, yeah, you kind of have to put it all in place, and then it becomes a little bit easier to understand and to kind of not celebrate, but at least have a little bit of joy after a match like that."
Clijsters hadn't competed at the U.S. Open since winning the 2005 championship. Now she will play for her second career major title Sunday against No. 9 Caroline Wozniacki of Denmark, who beat Yanina Wickmayer of Belgium 6-3, 6-3 in the other rain-delayed women's semifinal.
Williams came into the day having won three of the past four Grand Slam titles, and 30 of her previous 31 matches at major tournaments.
She was playing fantastically at the U.S. Open, not losing a set before Saturday and having lost her serve a total of three times through five matches.
But Clijsters - who beat Williams' older sister, No. 3 Venus, in the fourth round - was superb, matching strokes and strides with as strong and swift a woman as the game has to offer.
Williams, meanwhile, kept making mistakes, and two backhand errors plus a double-fault contributed to a break at love that put Clijsters ahead 4-2.
When Williams netted backhands on consecutive points at 5-4, Clijsters had broken her for the second time and taken the opening set. The last backhand was the 14th unforced error made by Williams to that point - twice as many as Clijsters - and the American bounced her racket, caught it, then cracked it against the blue court, mangling the frame.
When Williams walked to the changeover, she clanged it against the net post and was given a warning for racket abuse by the chair umpire.
That would prove pivotal about an hour later, at match's end.
"I mean, the timing is unfortunate, you know," Clijsters said. "To get a point penalty at the time, it's unfortunate. But there are rules, and you know, like I said, it's just unfortunate that it has to happen on a match point."