KEY BISCAYNE, Fla. -- Two-time champion Victoria Azarenka withdrew from the Sony Open before her opening match Friday because of a lingering right ankle injury.

The third-ranked Belarusian was replaced by lucky loser Lauren Davis of the United States.

The same injury forced Azarenka to withdraw before her quarterfinal match a week ago at Indian Wells because of inflammation and tendinitis.

Earlier this week, the third-ranked Azarenka was optimistic she would play. On Friday, she released a statement saying she's "been working very hard to rehab" her ankle, but "it is still not fit to play."

Azarenka won the tournament in 2009 and 2011.

Azarenka is 17-0 this year with two titles.