Chelsea boss Graham Potter has said some of the club's new signings need to adapt to the Premier League, with the club's January spending spree yet to turn around their poor form.

Chelsea were held to a 1-1 draw against West Ham United on Saturday, with Atletico Madrid loanee Joao Felix scoring his first goal for the club before former Chelsea fullback Emerson levelled the game shortly after. The result means Chelsea have won just once in their last eight matches in all competitions.

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In his postmatch news conference, Potter said Chelsea's progress is being halted by a list of issues, including his new signings needing time to adapt to England's top-flight.

"I just said from a performance perspective I thought it was [an improved performance]," Potter said.

"You can also see the potential of the team but you can also see where the work is, which is getting Reece James up to speed, which is getting Ben Chilwell up to speed, which is getting Ruben Loftus-Cheek up to speed, which is getting Wesley Fofana up to speed, which is getting N'Golo Kante up to speed, which is adapting [Myhailo] Mudryk into the Premier League, which is adapting [Noni] Madueke into the Premier League, which adapting Benoit Badiashile into the Premier League, which is adapting Joao Felix into the Premier League.

"That's just how it is, that's the way I see it and I'll just be honest to say how it is but I completely understand that people are frustrated if you don't win."

Chelsea made eight signings in January and, due to their inflated squad, had to leave defender Badiashile and striker Pierre-Emerick Aubameyang out of their Champions League roster.

Potter said that managing a squad of that size is a challenge but also described the situation as "exciting."

"I think it's a challenge but it's my job," he said. "It's exciting, it tests you because you have to make sure you communicate properly and manage the environment because otherwise it can go not very positive, but it's been a good training week.

"Then you have to have honest conversations and respect the fact that players will be disappointed, because that's normal."

Chelsea are ninth in the Premier League table after Saturday's draw and restart their Champions League campaign at Borussia Dortmund on Wednesday.