Arsenal midfielder Santi Cazorla has claimed that the team's changed mentality helped them to their 3-0 victory over Manchester United on Sunday.

The Gunners raced into a three-goal lead inside the opening 20 minutes at the Emirates Stadium thanks to a brace from Alexis Sanchez and a goal from Mesut Ozil.

Cazorla has said that Arsene Wenger's men were looking to deliver a response to their Champions League defeat to Olympiacos in midweek.

"We needed to believe after the loss against Olympiacos. We needed to change the mentality and the team was very compact and focused for the game against a big team," Cazorla told Arsenal's official website.

"This is the most important thing for the team. It was very important for us. Together we played very well. Three points is very important for us and we need to keep at the same level in the next game.

"We need to play together and in the first half we did very well and this is vital for us."

The victory has moved Arsenal ahead of United into second place in the Premier League.