The Gunners face United in the FA Cup quarter-final on Saturday, fresh from their controversial CL defeat at Barcelona on Tuesday night.
Boss Arsene Wenger and midfielder Sami Nasri have been charged by UEFA over comments made to referee Massimo Busacca over his handling of the game.
Striker Robin Van Persie was sent-off at the Nou Camp for kicking the ball away and has been told he can’t appeal the Busacca decision.
Wenger is still fuming over his team’s treatment in Spain but Wilshere is adamant they must turn that pain into a gain as they take United on head-to-head in the Cup and the Premier League title race.
“We are still in two competitions, just three points behind Manchester United in the league and with a game in hand,” said the teenage England midfielder.
“Maybe now that we are out of Europe, we can be stronger in the league, concentrate on that more, really push on to try to win the title.
“We know Manchester United are a great team, but they have a European game next week, so they might play a weakened side, then we can go there and take advantage of that.
“We have got great mental strength, there is disappointment in the dressing room, yes, but we have got to pick ourselves up and go to Manchester United to get the win.
“Then we need to be strong now in the league, to push on and make sure we get a trophy at the end of the year.
“We want to win every game. When United come to us, we want to be in front of them, hopefully we will be.”