Sir Alex Ferguson says Martin O'Neill can transform Aston Villa into a top four club this season.

Victory at Arsenal last week took Villa level on points with Arsene Wenger's team and Ferguson says they have the potential to qualify for the Champions League.

"They can finish in the top four," Ferguson said. "They are level with Arsenal and not far behind us, which is a good position to be in. It will be interesting because it is such a competitive league.

"Without question, Martin O'Neill is one of the best managers in the game. The only way you can judge managers is how they prove themselves over a period. And the job he has done at Leicester, Celtic and now Aston Villa makes him an obvious top manager."

United have used 27 players in the Premier League this season, the most of any team, while Villa, have used the least, fielding 17 players. And Ferguson can see the positives of O'Neill sticking with a settled side.

"He has built up a squad over the last couple of years that allows him consistent team selection," Ferguson said. "He doesn't make many changes and sticks by his format all the time."

Of their last 12 visits to face Villa, United have emerged victorious 11 times. They have also won twice in the FA Cup there, including the epic 1999 replay triumph over Arsenal. "It just seems to be a ground that suits us," Ferguson said. "We play well there. It is not a matter of being lucky, as you are at some grounds."