US tennis star Serena Williams will become the World No.1 women's player as soon as the new WTA rankings are announced on Monday.

Williams ensured her top spot by coming from a set down to beat Czech player Petra Kvitova 3-6, 6-3, 7-5 in the WTA quarterfinals in Doha, Qatar.

“Thanks everyone for all the support. Back to number one and it feels so good,” Williams wrote on her Twitter page afterwards.

The American, who’s now 31 years and four months old, will become the oldest women's World No.1 in the game’s history.

The younger Williams sister previously topped the Women’s Tennis Association rankings in the 2002 season.

Serena will replace Victoria Azarenka as world’s best player, with the Belarusian also making it to the semis in Doha after a 6-2, 6-2 win over Italy’s Sara Errani.    

Her return to the top has been no walk in the park, as she survived an emergency surgery in 2011 after her life was put at risk by hematoma and a pulmonary embolism.

But the American bounced back in spectacular fashion, dominating the 2012 season with victories at Wimbledon, the US Open and the London Olympics.

Next on Williams’s agenda is Russia’s Maria Sharapova, whom she will face in the in the Qatari semifinal.

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