Marouane Fellaini
Fellaini is open to a centre half move. (Reuters)

Manchester United midfielder Marouane Fellaini believes he is at his most effective when deployed as a defensive midfielder, but could have his eye on moving back to centre half later in his career.

The Belgian international became accustomed to playing as an attacking midfielder during his seasons at Everton where his physicality and goal threat was often put to potent use by David Moyes.

After following the Scot to Old Trafford on transfer deadline day for a fee of £27.5m, the 25-year-old has reverted back to a deeper role in attempt to strengthen his new club's frailties in the middle of the park.

But in an interview with FourFourTwo magazine, Fellaini revealed he has been previously utilised in a variety of positions across the pitch including in the back four, a position he would be open to picking up once again somewhere down the line.

"As a young player I played up front, on the wing, in midfield and when I started in the reserves at Standard Liege I played centre back," Fellaini said.

"It was a good position for me because I am tall and good in the air but I can also pass the ball. Maybe it is a position for me in the future?"

In his two starts for United against Bayer Leverkusen and Manchester City, Fellaini has operated alongside Michael Carrick, with Tom Cleverley's start to the season peppered by injury and Anderson yet to earn himself a consistent starting role in midfield.

While Darren Fletcher looks to be taking steps closer to returning after his battles with ulcerative colitis disease, Moyes is still short on midfield numbers and the United boss may need Fellaini to sacrifice his attacking qualities for a more defensive role, something the Belgian believes he is already accustomed to.

"My best position is defensive midfield," Fellaini continued. "During the last few years with David Moyes I played further forward and I scored some important goals, which is why he kept me there and I liked it because I was young and learning."

United will take on Ukrainian champions Shakhtar Donetsk in their second Champions League group game on Wednesday night having lost their previous two Premier League games.