Sunderland v Arsenal: Arsene Wenger admits Champions League thrashing by AC Milan will always haunt him It was the kind of watershed performance that should crystallise Wenger's thoughts regarding change at the club, should he carry on beyond this campaign. Already the future of several first-team players is in some doubt, especially in the case of Theo Walcott, Andrei Arshavin and Tomas Rosicky, whose contracts expire within 18 months. Arsenal will also consider offers for Marouane Chamakh and Sébastien Squillaci. They hope to sell other fringe players such as Nicklas Bendtner, Carlos Vela, Denilson and Manuel Almunia. The bigger question for the club is whether Robin van Persie can be persuaded to extend a contract that expires in 2013. That appears increasingly unlikely. Wenger must hope to attract the talent that will persuade Van Persie - and players such as Jack Wilshere - that Arsenal can become competitive again. That starts with attempting to win the FA Cup, the most recent trophy they have won, back in 2005. Defender Johan Djourou said the players would be motivated by the defeat in last season's Carling Cup final. "This is a big opportunity," he said. We were very disappointed about what happened last time at Wembley and we want to put that right. It is still in our heads. The club's ownership may return to focus this summer, with Uzbek billionaire Alisher Usmanov having bought another two pockets of shares this week as he moves close to acquiring 30 per cent of Arsenal, at which point he will have increased access to information regarding the club's financial status. Usmanov is in the market to buy again, although he will not pay more than £14,000 a share. The club's major concern, however, involves qualifying for next season's Champions League. "We lost against a good Milan team, not an exceptional one," Wenger admitted, although his contention that Arsenal were "punished severely" might not ring true. Arsenal could have been defeated more heavily. Wenger said that, against Sunderland, it was vital to "respond in a positive way and ensure we have the mental qualities to be at this club," adding: "We are in fourth position and we have an opportunity to qualify for the quarter-finals of the FA Cup. It is important that we are up for that match and do not feel sorry for ourselves because of that performance. It can still be a positive week and we will see how we deal with the Milan game in the second leg later. What is important now, is not only the FA Cup, but also our response. The mental attitude of our team is at stake. That is very important.