New Sunderland manager Chris Coleman has warned his players to change their attitude or leave the club as he targets an instant turnaround in form.

The 47-year-old was confirmed as the Black Cats' 10th permanent boss since December 2008 on Sunday afternoon, taking over from Simon Grayson who left the North-East outfit in the bottom three.

Coleman admits that he faces an uphill struggle in his attempt to halt back-to-back relegations to League One, but he is relishing the challenge and wants to quickly put his mark on things at the Stadium of Light.

"If you're committed you're in, if not you're out. You can't pretend at it. What we don't need are any shrinking violets," BBC Sport quotes him as saying on the topic of his underperforming players. "We will find out who is going to be coming along on this next chapter pretty quickly I think. Whoever is not will need to go and play football somewhere else.

"If this challenge is too big for them then they need to move on. Nothing good ever came from a comfort zone and I know I'm in no comfort zone at Sunderland. Someone will turn this club around, whether it is me or the next one. I want that to be me, of course. You can go through a career as a manager and never manage a big club. I always wanted that experience and here I am.

"We are bottom of the league, that's reality. It's still a big club, still Sunderland. It is going to be a big challenge. I am going to need all the supporters, players, staff, everybody to come with me on this. Sooner or later it will start turning. Then it is such a big club that when we gather momentum, it's hard to stop."

Sunderland head to promotion-chasing Aston Villa on Tuesday night for former Wales boss Coleman's first game in charge.