Van Persie returns to squad for Arsenal
The news is a welcome boost for the Gunners, who lost the first leg at Old Trafford 1-0, after Croatian forward Eduardo was ruled out for three weeks with a groin problem.
Van Persie has also been struggling with groin trouble and has not played since Arsenal's 2-1 FA Cup semi-final loss to Chelsea.
But the Dutchman has returned to training ahead of the second meeting with European champions United and could partner Emmanuel Adebayor in attack as boss Arsene Wenger considers a 4-4-2 system.
Silvestre, meanwhile, was a doubt after he picked up a groin injury versus his former club but could now be in contention to feature.