Chelsea manager Mauricio Pochettino says the club are attempting to sign a new attacking player following the injury to Christopher Nkunku.
The France forward, 25, will be out for "an extended period" after undergoing surgery on his injured left knee.
Nkunku suffered the blow during a pre-season friendly against Borussia Dortmund in Chicago.
"We are working in the market because we are going to miss an offensive player like this," said Pochettino.
"The club is working, trying to find a solution for maybe short term, medium and long term to add the right profile for the team to perform from now.