SUNDERLAND will confirm the signing of Chelsea youngster Jake Clarke-Salter in the next 24 hours, with Chris Coleman admitting this month’s transfer window will ‘make-or-break’ his club’s chances of avoiding relegation to League One.

Clarke-Salter, a 20-year-old centre-half, has agreed to join the Black Cats on loan for the remainder of the season and should be available to make his Sunderland debut in Saturday’s Championship game at Cardiff City.

A member of England’s World Cup-winning Under-20s squad last summer, Clarke-Salter was set to travel to Wearside on Friday, only for Chelsea boss Antonio Conte to opt to keep him for an extra weekend in order to name him in his squad for Saturday’s FA Cup third-round tie against Norwich City.

Clarke-Salter was an unused substitute as Chelsea claimed a goalless draw at Carrow Road, but Sunderland officials are confident Conte will not decide to retain him again for the replay.

Instead, the defender is set to become Coleman’s first signing of a transfer window that will go a long way towards determining whether Sunderland are able to survive in the Championship.

“I have to emphasise that this will be a big window for us in terms of adding to what we’ve got,” said Coleman, in the wake of his side’s FA Cup third-round defeat to North-East rivals Middlesbrough. “It’ll be a very big window.

“We must (make signings), and if we don’t get what we want, it won’t be for the want of trying. The thing is though, we won’t be the only club trying.

“Some players we’re looking at, there’s a host of other clubs looking, too. Eventually, it won’t be a money thing – it’ll be a player thing. Do you go there, or do you go somewhere else to fight for something different? That will be out of our hands.

“We’re not financially strong, but on the flipside of the coin, players who come to us are going to get a lot of football. Players who are a bit younger, looking for experience, if they go to a club at the top of the league, they might only get 50 per cent (of their time in the team). They can come to us and get 70 or 80 per cent, and that experience is valuable.”

Coleman continues to discuss Ben Woodburn’s future with Liverpool, and is hopeful the teenage striker could receive the green light to move to Wearside within the next seven days.

Jurgen Klopp had expressed reservations about losing Woodburn in the immediate aftermath of Phillipe Coutinho completing a £142m move to Barcelona, but with Mo Salah expected to return from injury before the weekend and no FA Cup third-round replay to worry about, the Liverpool boss is set to discuss the situation with Sunderland officials this week.

Ideally, Coleman would like to make four or five additions before the transfer window closes, but with Ellis Short refusing to invest any new funds, his ability to recruit players will be heavily influenced by what happens in terms of outgoings.

Lamine Kone and Didier Ndong are available to the highest bidder, but with both players currently nursing injuries, Sunderland are yet to receive a formal offer for either.

Coleman was deprived of 11 senior players at the weekend, and while some, such as Duncan Watmore and Lee Cattermole, are nursing long-term problems that could not be helped, the Sunderland boss has hinted that others are not doing everything they might in an attempt to make themselves available for action.

“One or two of them are out for a few months and have scans, but could one or two be doing a bit more to be with us? Yes,” said Coleman. “My conscience is clear – I’m ready for what’s in front of me and I won’t always come out on top, but I never duck it – so you’ll have to ask them that (question) I think.

“We’re in a dogfight, and you don’t go into a dogfight with kittens, that’s for sure. I just need whoever is ready for it, and the boys were ready (against Middlesbrough).

“We were naïve and nervous, but at least they were out there having a go. These are the players we need, and they need support in terms of strength and depth.”

While Coleman accepts his current squad lacks quality in a number of areas, he has consistently refused to criticise the attitude and commitment of the players he has been able to select in the last few weeks.

It would be wrong to suggest that his team are not playing for him, but he concedes they desperately need reinforcements if they are to successfully address a position that currently sees them sitting in 23rd position in the Championship table.

“Before I arrived, I looked at the squad and thought, ‘Okay, there’s five, six, seven players out missing’, but now it’s 11,” said Coleman. “It amplifies the challenge, especially if we don’t get better than that in terms of numbers and quickly establish who wants to be here and in a relegation dogfight.

“Who wants to help out in the spotlight with all the pressure and take responsibility? We need to help the boys that are out there at the moment, and get some boys back from injury while getting some fresh faces in.

“We’re working hard to do that, and we realise it's something we need to do. We absolutely must do that, otherwise the challenge is even bigger.”

Sunderland’s need for attacking additions became even more acute on Friday when Lewis Grabban completed his return to Bournemouth.

The striker requested to return to his parent club despite scoring 12 goals in the opening half of the season, and is now expected to make a permanent move away from the Vitality Stadium before the transfer window closes. Ironically, Sunderland’s weekend opponents, Cardiff, are one of the clubs to have already made formal contact with Bournemouth officials.

“I think Lewis will move on in this window, but who it will be and when, we don’t know,” said Cherries boss Eddie Howe.

Coleman accepts the need for a replacement for Grabban, but has questioned the extent of the striker’s input in a Sunderland shirt despite him having scored nine more league goals than any member of the current squad.

“He got a lot of goals, but we didn’t get a lot of wins if you look at the stats,” said the Black Cats boss. “Consolations and penalties are fine, he’s a natural goalscorer, but we won one game in 16.

“You don’t want to lose that, but that’s up to him and if he doesn’t want to be with us, fine. Why should I get down on my hands and knees to get somebody to stay at Sunderland, even though we’re bottom of the league? He goes back to Bournemouth and we get on with it.

“If anybody wants to be in this fight with us between now and the end of the season, you’ve got to make sure you’re all in. You can’t just dip your toe in the bathwater when you feel like it.”

Birmingham’s progress to the FA Cup fourth round means Sunderland’s scheduled trip to St Andrew’s on January 27 has been postponed.