Bill Gates usually isn't much of a celebrity sports fan, but there he was Sunday in London's ExCel Arena, watching 16-year-old Ariel Hsing try to do the unthinkable. In a third-round match of Olympic table tennis, Hsing pushed China's heavily-favored Li Xiaoxia to the brink. Hsing eventually lost the best-of-seven series in six games, 11-4, 9-11, 11-6, 6-11, 11-8, 11-9.

Hsing and Gates were introduced by Gates' friend and fellow billionaire Warren Buffett seven years ago at an investors meeting. Hsing has become close with both Gates and Buffet, calling them "Uncle Bill" and "Uncle Warren," respectively. The duo has invited Hsing to several Berkshire Hathaway shareholders meetings, where they have faced off in table tennis.

Despite Hsing's loss Sunday, Gates came away very impressed.

"Nothing short of phenomenal," Gates said. "She is amazing."

Hsing, who attends Valley Christian High School in San Jose, didn't notice that Gates was among the spectators.

"I only found out he was here when someone told me a minute ago and it took me by complete surprise," Hsing said after the match. "I was just really happy to see him and I really appreciate him coming over. He is such an important person and him coming to watch is the most important gift he could give."

This is Hsing, Gates and Buffet having some fun this spring. Even with the humongous racquet, Buffet didn't stand a chance.

-- Follow Robbie Levin on Twitter @RobbieLevin.

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