Mauricio Pochettino has admitted Chelsea could be forced into signing a new striker during the current transfer window due to uncertainty over the extent of Christopher Nkunku’s hip injury.

The France forward has made only one Premier League start since joining from RB Leipzig in the summer for £51m and has been absent from training for the last 10 days after suffering the injury before the FA Cup third-round win over Preston. Pochettino revealed Nkunku is set to be assessed in the coming days and admitted he is worried about the extent of his injury given that his other main striker, Nicolas Jackson, is away at the Africa Cup of Nations with Senegal.

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“It’s true that now in the next few days we are going to see the situation,” said Pochettino. “That’s why I told you that I am a little worried. I still don’t have all the information about whether he is going to be available or not for a small initial period. We need to be very clinical to take some decisions to think and see how we fix the problem.”

Nkunku’s absence would mean Armando Broja is the only fit striker available to Pochettino for Saturday’s meeting with Fulham at Stamford Bridge, although Ben Chilwell and Benoît Badiashile are in contention again after long-term injuries. The Ivory Coast forward David Datro Fofana is expected to join Burnley until the end of the season after cutting short his loan move to Union Berlin. Chelsea have been tracking Brentford’s Ivan Toney and Victor Osimhen of Napoli, although moves for either appear unlikely this month unless they can sell players such as Conor Gallagher.

Pochettino acknowledged that the 22-year-old Albania striker Broja, who scored the opening goal against Preston but missed most of last season with a knee injury, will have to shoulder the goalscoring responsibility for now. “[He] needs to now play three games in a row and that’s difficult for him,” said the Chelsea manager. “All of these situations make our job a little more difficult. I’ve said before that it is an exciting project but situations like this make it more difficult to change the situation and grow at a different pace.”

Were Pochettino to extend his personal 100% record against Fulham to a seventh match, Chelsea could find themselves in the top eight. It would also mean the Argentinian surpasses his predecessor Graham Potter’s 12 victories at the club. That it will have taken the former Tottenham manager only four fewer games than the 31 Potter was granted before being sacked hints at slight progress.

Pochettino insists his side can overturn a 1-0 deficit against Middlesbrough in the Carabao Cup semi-final second leg a week on Tuesday. But the midfielder Moisés Caicedo appeared to have given his manager some incorrect information when discussing the Championship side, having apparently told Pochettino that his Brighton team had lost to them in the FA Cup last season when, in fact, they had won 5-1 at The Riverside.

“If you see the previous years, other Premier League teams went out to Middlesbrough,” said the Chelsea manager. “It was Caicedo telling me that ‘we lost last year to Middlesbrough with Brighton’ and many Premier League teams, when they play in the cups there, they lose.”

Nonetheless, Pochettino believes his side are starting to show more consistency, having recorded three straight wins before their midweek defeat by Michael Carrick’s side.

“Every single game should be a priority for us, we need to play every game like a final,” he said. “We are a young team so it is difficult to be consistent and perform the same way in every game but we try. That is the process. We knew it was going to happen but dealing with that is the most important thing. Some situations that we didn’t expect have made it more difficult. We are really calm, we know what we need to do. With time I think we are going to be very successful here. No doubt.”

Meanwhile, Chelsea are also interested in signing the Palmeiras youngster, Estêvão Willian. The club have scouted the 16-year-old winger, who is nicknamed “Messinho”, and reports in Brazil have claimed they are ready to trigger the player’s €60m release clause.