By Julien Pretot
PARIS (Reuters) - Victoria Azarenka suffered a shock early exit at the French Open when she slumped to a 6-2 7-6 fourth-round defeat by Slovakian 15th seed Dominika Cibulkova that put her world number one status at risk on Sunday.
Belarussian Azarenka, who lost the tiebreak 7-4, will lose her world number one spot to Maria Sharapova if the Russian second seed reaches the final.
Cibulkova, who reached the semi-finals at Roland Garros in 2009, threw her racket and fell on her back after ending Azarenka's run with a backhand crosscourt passing shot after one hour and 47 minutes.
She will next meet either American teenager Sloane Stephens or Australian sixth seed Samantha Stosur.
Azarenka started by winning a 15-minute opening game featuring six break points on the Slovakian's serve but she could not sustain the pace, dropping her serve three times.
She tried hard to find angles but the ball would too often land long or wide on the important points.
Cibulkova put her opponent on the back foot with lengthy rallies from the baseline, taking a well deserved one-set lead after 44 minutes.
The second set was a topsy-turvy affair on a chilly afternoon on Court Suzanne Lenglen.
Azarenka opened a 2-0 lead, only for Cibulkova to reel off four games in a row to close in on victory.
Cibulkova, however, struggled to keep a check on her nerves.
She double-faulted on break point in the following game and Azarenka went on to break in the 11th game when the Slovakian netted a crosscourt backhand.
But Cibulkova hit back to force a tiebreak.
She set up three match points, with Azarenka saving the first one at the end of a spectacular exchange at the net, but she was left with her feet stuck on the clay on the second.
(Reporting by Julien Pretot; Editing by Pritha Sarkar)