French Open: Injury ends Azarenka's comeback in first round

Victoria Azarenka's renaissance suffered a setback on Tuesday when the former world number one, hampered by a knee problem, pulled out of the French Open during her first-round match.

The fifth seed from Belarus finally called it a day when trailing 6-3 6-7(6) 4-0 against Italian Karin Knapp.

Azarenka, who had begun to look back to her best this season after two injury-ravaged years, had opened up a 3-1 lead in the first set before world number 118 Knapp stepped up a gear and won five games in a row.

She called on the trainer at 3-3 in the second set after locking her right knee in the previous game.  At 5-5 she could barely serve and smashed her racquet on the court in frustration. She still managed to force a tiebreak, which she won 8-6 after saving a match point. But it went downhill from there and Azarenka threw in the towel after four games in the decider.