Bacary Sagna has backed Manchester City teammate Eliaquim Mangala to become one of the world's finest defenders and vows to help his "twin brother" reach that level.

The 23-year-old sealed a £32m move to Eastlands from Porto in the summer but came in for criticism over his performance in last month's 4-2 win away to Hull City.

Sagna admits that Mangala is a little rough around the edges but claims that his fellow Frenchman has the potential to reach an elite status in the game.

"He has everything he needs to be a top player and I'm sure he will be. To me he will be one of the best defenders in the world, but he's still young and there's a lot of room to improve," the right-back told ESPN.

"I'm everything to him. He's like my twin brother, my son. I see him more than I see my family, so our relationship is really important.

"It's my responsibility to help him. I remember when I came here I didn't speak proper English. But he's a lovely guy and he's settled in well."

Mangala has made four appearances for the Citizens so far this season.