Sunderland manager David Moyes has backed John Stones to put his shaky start to life at Manchester City behind him and become one of the top defenders around.

The England international has not yet lived up to his £47.5m price tag since joining from Everton last summer, often being accused of overplaying from the back.

Moyes, who brought Stones to Merseyside from Barnsley for a minimal fee in 2013, expects the centre-back to add to his all-round game with time and eventually go on to emulate former Manchester United defender Rio Ferdinand.

"If you look at him, you'd say he is a good footballer," he told reporters. "Is he yet to become an absolutely top defender? Yes, he's still got to do that.

"He's not John Terry, he's not Jamie Carragher but he's got bits of a young Rio Ferdinand in him. I think he can become a really good centre half in time.

"As he gets older, he will develop those defensive instincts because maybe that is one of the question marks against him at the moment. But as a type, as somebody who wants to do the right things and improve all day long, he's got that."

Stones has featured 21 times for City in the Premier League this season and is expected to start against Sunderland on Sunday afternoon.