The Brisbane star climbed to number four in the world yesterday, despite a disappointing loss to Serbian Jelena Jankovic 6-3, 5-7, 7-6 (7-4) in the quarter-finals of the WTA event in Dubai on Saturday.
She is the first Australian-born player to have reached fourth in the WTA standings since Wendy Turnbull in 1985.
Although celebrating her new world standing, Stosur will turn her focus to combating her run of tight losses to avoid a plummet in rankings later on in the year.
Her loses include not only yesterday's fall to Jankovic, but also loses to the Italians Francesca Schiavone and Flavia Pennetta in Australia's Fed Cup quarter-final in Hobart this month and also close loses last month to Svetlana Kuznetsova in Sydney and to Petra Kvitova at the Australian Open.
With so many near chances it's obvious that the pressure is now on Stosur to raise her game and defend her position that was awarded after a stellar claycourt season in 2010.
Caroline Wozniacki, who reclaimed her world number one standing from Kim Clijsters last week, celebrated her return to the coveted spot with the 13th title of her career, defeating Svetlana Kuznetsova 6-1, 6-3 in the Dubai Open yesterday.
Denmark's Wozniacki showed her return to form with the final finishing up five dolid wins in the lead up to the match against Kuznetsova.
Wozniacki broke serve immediatly for 2-0, and went on to break it twice more to capture a one-sided first set in only 30 minutes.
"I was very happy with my performance," Wozniacki said.
"I went for my shots and I am definitely playing better than I have before."
In men's tennis top seed Andy Roddick took out his 30th career ATP title, defeating Milos Raonic 7-6 (9-7), 6-7 (11-13), 7-5 in Memphis yesterday, denying the Canadian his second title in as many weeks.
The world number eight ranked Roddick, fired 20 aces against Raconic taking out the game.
Roddick now joins Jimmy Connors and Tommy Haas as three-time winners at the indoor tournament, which was played alongside a WTA women's event that was held in Dubai.