Successor as Wales manager must be passionate Welshman, says Chris Coleman
New Sunderland manager Chris Coleman has warned the size of the challenge he faces means he will quickly get rid of players he feels lack commitment.
Coleman, 47, left his job as Wales boss to sign a two-and-a-half-year deal to succeed the sacked Simon Grayson.
He admits it is a "daunting task" with Sunderland bottom of the Championship.
"If you're committed you're in, if not you're out," said the former Fulham boss."You can't pretend at it.What we don't need are any shrinking violets."
He added:"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."
'When it turns it will be hard to stop'
Coleman is Sunderland's 10th permanent manager since Roy Keane's exit in December 2008 and he will be joined at the Stadium of Light by Kit Symons, who was his assistant at Wales.
He says friends in the game told him not to visit the club's training ground and stadium until he was sure about taking the job to prevent the high-quality facilities from swaying his judgement.
But he inherits a club that were relegated from the Premier League last season and set an English football record of 20 successive home games without a win following Saturday's 2-2 draw with Millwall.
"Nothing good ever came from a comfort zone and I know I'm in no comfort zone at Sunderland," added Coleman, who will take charge of Tuesday's trip to Aston Villa.
"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."
From Fulham to Athlitiki Enosi Larissa
Chris Coleman:Farewell to a Welsh managerial hero
Welshman Coleman finished his playing career at Fulham in 2002, but stayed at Craven Cottage to join the coaching staff.
He took over from manager Jean Tigana in April 2003 on a caretaker basis and helped the side avoid relegation from the Premier League and was consequently rewarded with the full-time role.
He led the Cottagers to ninth place in the Premier League in his first full season in charge, but was eventually sacked in April 2007.
Spells at Real Sociedad, Coventry City and Greek side Athlitiki Enosi Larissa followed before he was appointed as Wales manager in January 2012, two months after the death of predecessor Gary Speed.
Former defender Coleman guided Wales to the semi-finals of Euro 2016 but he arrives at the Stadium of Light after they failed to qualify for the 2018 World Cup.
What is it like to manage Sunderland?
Former Black Cats manager Simon Grayson on BBC Radio 5 live's Sportsweek
I don't think the club is unmanageable but it is a big proposition for anybody because of the name, where it's been, the fanbase etc.What we found more difficult than I realised was trying to transfer the positivity from the training ground to the Stadium of Light, where there has been a lot of negativity and poor results over the years.
I met him [owner Ellis Short] when I was interviewed for the job and at the first game of the season and that was the last I heard or saw of him.He moved to America.In his defence, he has put £250m into that club and is still funding it now.
That's a hell of a lot of money.It has been mismanaged for many different reasons and there has been a lot of money wasted over the years.Certainly, there comes a point where maybe enough is enough for somebody.
The biggest thing Chris will need is time because it just doesn't happen overnight when a club has been through some real dark stages.Looking from the outside, he will know there is something wrong somewhere because of where they are.
He will go to the training ground and see huge facilities and an absolutely brilliant venue to go and work every day but it's what happens on the grass that matters.
Former Arsenal defender Martin Keown on Football Focus
I think Chris is now ready for this job.He did a fantastic job for Wales and now he needs a new challenge.But Sunderland are in all sorts of trouble.That club is on a slippery slide, it needs correcting urgently.
Former Liverpool defender Mark Lawrenson on Football Focus
They are in all sorts of trouble because look at the managers that they've had who haven't been able to turn it around.I thought Chris would have waited a little bit longer to get a club in a better position - but that is one heck of a job....