Former Manchester United coach Rene Meulensteen has suggested that Wayne Rooney is "not totally himself" at the moment.
The 30-year-old striker has netted just two Premier League goals so far this season, which has led to supporters and critics to suggest that he is in decline.
However Meulensteen, who was a coach at Old Trafford from 2007 to 2013, has suggested that Rooney is struggling due to the style of play that manager Louis van Gaal has introduced.
"You can't throw it all at Wayne himself, it's a combination of a few things," he told talkSPORT. "Wayne is an adventurous player who likes to have freedom on the pitch, to roam around and get involved and find his own way to get into the game.
"I think at the moment he's a little more restricted, he doesn't always get the ball when he wants it and where he wants it. Manchester United are going through a transformation from the style Sir Alex Ferguson liked to play.
"He wanted to play with a lot of creativity, a lot of freedom and, at times, risk, but now under Louis van Gaal it's much more calculated. It's more about working your way up the pitch, it's more laboured and more pedestrian. Wayne's stats in the derby may have looked poor, but a lot of players' stats also looked poor. But I do feel that he is not totally himself when I see him play at the moment."
Rooney failed to find the net as United played out a goalless draw with rivals Manchester City on Sunday.