Aston Villa boss Alex McLeish admits he has no idea why former Wigan Athletic winger Charles N'Zogbia has flopped.

N'Zogbia returns to Wigan today for the first time since his £9.5million move to Villa Park last summer.

McLeish, who clashed with the player after substituting him at Newcastle three weeks ago, said: "That's the 64,000 dollar question.

"Why has Stewart Downing failed to settle down at Liverpool? Why has Andy Carroll been slow to settle?

"It's just one of the mysteries of football. It's baffling when you know they're great players. But who knows what goes on in their mind?

"At the end of last season with Wigan, I thought Charles was the guy who made the difference for them.

"And if he can bring that to us at a consistent level, he is going to make a name at Aston Villa."