Arsenal boss Arsene Wenger admits Gabriel Paulista is facing three weeks out with a hamstring strain.

Gabriel pulled up during victory at QPR in midweek.

"It's a special intensity because it's between two teams with a chance of winning," Wenger said. "We're focused on the FA Cup.

"We are the holders of the FA Cup and we want to keep it. The cup is about giving it all on the day and we'll do that on Monday.

"We are confident. We go to Manchester United to qualify and give absolutely everything with hard work and team effort."