The French pair is set to be out for three weeks, which means they could miss Premiership games with Bolton, Hull and Everton.

"Unfortunately we have lost William Gallas with a hamstring problem," Wenger told Arsenal TV.

"We lost Silvestre too with a thigh problem last week. I think Gallas and Silvestre will be out for three weeks."

Despite the blow, Wenger welcomes back Kolo Toure and Denilson, who are both fit to face Wanderers on Saturday.