(CNN) -- Maria Sharapova has been forced to pull out of the WTA Rogers Cup tournament in Toronto next month, still plagued by a nagging left hip injury.
Organizers of the prestigious hard court tournament announced Sunday that the four-time grand slam champion had withdrawn from the event that starts August 5.
World No.2 Sharapova has not played since sensationally losing to Portuguese qualifier Michelle Larcher de Brito in the second round at Wimbledon on the opening Wednesday.
"I am extremely disappointed that I am unable to play in Toronto next week as it's one of the best and most important tournaments of the year," the Russian said.
"I was looking forward to making a healthy return to the courts in front of my Canadian fans but unfortunately I'm just not recovered yet."
Sharapova, who recently took on former U.S. tennis legend Jimmy Connors as her coach, will be anxious to return as soon as possible with the U.S. Open looming.
She will be left with only two hard court tournaments at Cincinnati and New Haven ahead of the final grand slam of the season on the same surface at Flushing Meadows.
Meanwhile in ATP Tour action, Russia's Mikhail Youzhny won on the clay of Gstaad as he beat Dutchman Robin Haase 6-3 6-4 in Sunday's final.
It was the ninth Tour title for the 31-year-old, who has waited over 18 months to return to the winners' circle.
"I'm trying everything to try and play more consistently at a high level," he told the ATP Tour official website.
The tournament was marked by the early exit of home hero Roger Federer, with fellow Swiss and second seed Stanislas Wawrinka also following him out before the weekend action.
The Croatia Open title went to Spain's Tommy Robredo, who beat Fabio Fognini of Italy 6-0 6-3 in the final.
Victory for the fifth seed ended the Italian's 13-match winning streak which has brought him titles in Stuttgart and Hamburg.
Fognini made 31 unforced errors and said the efforts of recent weeks had caught up with him.
"I would like to apologize to the fans that I could not give more in the final, but I'm simply too tired from other matches," he admitted.