Serena Williams finally changed her story about the cause of her Wimbledon breakdown.

Sports Illustrated recounted Williams' ordeal in England over the summer when she was beyond disoriented during a doubles match with sister Venus three days after she lost to Alize Cornet in the third round at Wimbledon.

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Serena told SI that she stayed in bed for three days after her loss to Cornet, feeling "dizzy, dehydrated and feverish."

But the reason she decided not to withdraw from the doubles match?

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"I hate to let people down," Serena told SI. "I felt like, I don't want anyone to be upset thinking I pulled out because I lost [in singles]. I'm no quitter.

"I should have just taken that moment and said, 'What the heck are you doing? Just stay in bed today.' "

She said that Venus had begged her not to play in the doubles match - even though Venus did not appear the least bit alarmed when her sister couldn't hit a serve over the net at the beginning of the match.

According to SI, Venus had repeatedly told her sister during warmups to walk off the court. "I wanted her to put the racket away, but I tried not to be bossy," Venus said in her first statement on the matter, at last month's tournament at Stanford. "She kept saying, 'I want to try.' She tricked me into letting her try."

Serena's coach, Patrick Mouratoglou, who said at the time he hadn't seen her in two days, saw immediately that something was wrong with Serena when he watched her walk onto the court. SI reported that he motioned from the stands to a WTA official on the court and asked for a doctor and for the official to delay the start of the match.

Serena said she was drug-tested the day after the doubles match and has not been told she tested positive for anything.

"I have nothing to hide," she told SI. "No, I didn't take anything. If you want to ask me if I took drugs, I didn't take drugs. I'm not on drugs. I've heard it all. I'm not pregnant; I wasn't pregnant. Although I think a baby would be great, but there's a time and place for everything. But no, I don't do drugs. Never did 'em. I'm scared of 'em. I'm not on that stuff."

SI added that some of her fellow players were in the locker room "pantomiming Serena drinking."

"God, no," Serena responded, laughing. "I wish."

So her fear of letting people down contributed to, perhaps, the second most bizarre incident recorded in women's tennis (behind Monica Seles' stabbing in 1993). And though both Venus and Mouratoglou saw right away Serena was beyond disoriented, neither stopped the spectacle that took place.

Why do you think Serena Williams didn't forfeit her doubles match at Wimbledon? Comment below or tell us @SportsWN.