IT IS one of world sport's longest running feuds and now we finally know how it all started.
Maria Sharapova has lifted the lid on the bitterness between herself and Serena Williams, which has hung over the WTA for 13 years.
In an extract from her soon-to-be-released autobiography, Unstoppable: My Life So Far, Sharapova details how the relationship between the pair fell apart after the Wimbledon final in 2004.
A then 17-year-old Sharapova defeated Williams 6-1 6-4.
While things were initially pleasant between the two after the match, the mood quickly changed in the locker room.
"When the match was over, Serena hugged me," Sharapova wrote.
"She said something like 'good job' and smiled. But she could not have been smiling on the inside.
"What I heard when I came in to the locker room was Serena Williams bawling. Guttural sobs. I got out as quickly as I could, but she knew I was there.
"People often wonder why I have had so much trouble beating Serena; my record against her is 2 and 19. To me, the answer was in this locker room.
"I think Serena hated me for being the skinny kid who beat her, against all odds, at Wimbledon. But mostly I think she hated me for hearing her cry.
"Not long after the tournament, I heard Serena told a friend - who then told me - 'I will never lose to that little b**** again'."
Williams has been all but true to her word, losing to Sharapova once since that Wimbledon final.
That includes a 7-0 record in Grand Slam events.
Sharapova believes the rivalry between the two pushed Williams to even greater heights.
"Serena and I should be friends; we have the same passion. But we are not. I think, to some extent, we have driven each other. Maybe that's what it takes.
"Only when you have that intense antagonism can you find the strength to finish her off. Who knows? Some day, when all this is in our past, maybe we'll become friends."
Sharapova returned to the WTA Tour in April after serving a 15-month doping ban.
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