The goalkeeper sustained a shoulder injury while representing Senegal at the FIFA World Cup and has been unable to feature for the Blues since returning following a last-16 exit to England for the Lions of Teranga.

Kepa Arrizabalaga has deputised for the past two matches since the post-World Cup restart and will do so again when the champions visit Stamford Bridge on Thursday evening.

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‘He’s been training a little bit more than he was,’ reported head coach Graham Potter.

‘He’s not fully fit at the moment but hopefully in the next week or so he might make some progress.’

David Datro Fofana, Chelsea’s newest recruit, was in the stands watching on during our New Year’s Day draw at Nottingham Forest, and Potter discussed the plan for the 20-year-old in the coming days.

It was announced on 28 December that we had reached a pre-agreement with Molde FK for the youngster’s permanent transfer and that he would join the Blues once the winter transfer window opened at the start of January.

‘He’s here at the moment but we still need to wait for the clearances and all those formalities,’ he explained.

‘He’s been on a bit of a break so we’ll give him some time to train and assess him, then find out the best solution in terms of how to take the next step of his career.’

Potter revealed no decision had yet been taken on whether the Ivory Coast striker would go out on loan this month or stay among the senior squad at Stamford Bridge.

‘It’s too early to say. He’s an exciting player so we’re open-minded about it.’

Potter would not be drawn on any potential further activity in the winter transfer window, insisting that January was always a difficult market in which to find solutions, although he and the club would be doing everything to improve.

‘The problem is that if I answer it and I’m specific with the answer then every single player in that area will be linked with Chelsea so I have to dodge it,’ he said when asked which areas of the squad needed particular reinforcement.

‘I’m the head coach so my responsibility is to the players that are here and then we’ll try to improve in every window. January is a complicated one because it’s the middle of the season and in the meantime we have to deal with all the noise of Chelsea being linked with everybody.

‘I won’t comment on anyone who isn’t a Chelsea player but always my job is to help the players that are here and then support the club in terms of decisions they make in trying to improve.’

Man City are 11 points better off than the Blues after the opening 16 matches of the season, although they have faltered with five dropped points in their past three league games.

That provides encouragement for Potter and he has called on the home supporters to play their part in creating a lively atmosphere so typical of heavyweight clashes under the lights in SW6 over the years.

‘We have to play well ourselves, that’s the key,’ he added. ‘You have to understand the quality that they have and try to stop it, which sounds simple when I articulate it now but obviously in reality it’s not so straightforward.

‘They’re a top team but we can cause them a problem. We can be ourselves, try to play well and put them under pressure. We need to use Stamford Bridge and then see what happens.’