SL Benfica will be without Petit for up to six weeks after the midfield player sprained his left knee against Molde FC in Thursday's UEFA Cup second-round first leg.
The 27-year-old international has been ruled out of the return leg in Norway on 27 November, in which Benfica will seek to protect a 3-1 lead. In addition, he has also been withdrawn from Luiz Felipe Scolari's Portugal squad for the friendlies against Greece and Kuwait on 15 and 19 November having been called up to Scolari's squad for the first time.
"I'll have to rest and see how the situation progresses," Petit said. "I just hope I can return to the form I was in when I picked up the injury. This is the worst time to be out of action having been called up by Portugal, but it's they way things are."
'It could be worse'
Benfica physio Pedro Magro told journalists the injury could have been worst, saying: "At least no vital ligaments were affected. If that wasn't the case then Petit could have been out for a long time."
©UEFA.com 1998-2015. All rights reserved.