Serena Williams became No. 1 again in women's tennis on Feb. 15 and at 31, she is is now the oldest woman to hold the top ranking, according to The New York Times.

The tennis star snagged the top spot when she beat former Wimbledon champion Petra Kvitova (3-6, 6-3, 7-5) in the quarterfinals of the Qatar Open in Doha. Williams will uproot Victoria Azarenka at No. 1 after the rankings are officially announced next week. Former tennis star Chris Evert held the top spot back in 1985 shortly before her 31st birthday.

"I never thought I would be here again," Williams said. "Oh my gosh, I've been through so much. I never thought I would be here."

Back in 2010, shortly after winning Wimbledon, Williams endured two operations on her right foot after she cut it on broken glass. Soon after, blood clots were discovered in her lungs and the star injected herself with blood thinners. When the thinner shots formed a pool of blood underneath her skin, Williams had to go to the hospital.

While these injuries led her to lose her top ranking to Caroline Wozniacki in 2010, Williams rallied back to top form over the next two and half years. First Williams won Wimbledon in 2012, then she brought home an Olympic gold medal and finally snatched victories at both the U.S. Open and WTA championship.

The only match that Williams lost in 2012 was after her first-round exit at the French Open.

"There were often times that I never thought I'd play again. Then I thought I'd never be able to win tournaments or Grand Slams," Williams said. "No. 1 was so far off. It was always a dream, but I was No. 1 when tragedy struck, and it was just an awful thing to happen. So I'm happy that I'm back." 

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