Arsenal boss Arsene Wenger admits the 'big four' can be broken up this season.

The Gunners tactician has tipped Manchester City and Aston Villa to join Manchester United, Chelsea, Liverpool and his own club in perhaps producing a top six,. Going away from the traditional top four finishes the league is used to.

"City look like they have made some great signings and have a high-quality squad, but it can take teams three months or more to find the right balance and to click," Wenger said.

"Don't forget that Real Madrid finished second last season and have already a very strong squad - they are not rising from 10th like City will have to. And history is on the side of Real Madrid as well.

"But I think City will be there and be strong and remember that Aston Villa were challenging for the title (last season) until they faded in the last 12 games.

"When I arrived, Newcastle were there, at the top, and then it was Leeds," he said. "So I think the top four is not something that is set forever."