Chelsea manager Enzo Maresca revealed ahead of Sunday's game at Wolves that Romeo Lavia had suffered a fresh injury setback.
The 20-year-old midfielder has only started one game for the Blues since joining from Southampton in a £58million deal this time last year.
An ankle injury followed by a hamstring issue resulted in Lavia playing just once last season - a half-hour cameo in a 2-1 win over Crystal Palace in December.
He started in last weekend's 2-0 defeat by Man City and then featured again as a sub in the Europa Conference League on Thursday.
But Lavia was not in Sunday's squad due to an irritation involving his hamstring.
When asked to provide more information on Lavia's latest injury issue, Maresca said: 'Hopefully nothing too serious.'
Chelsea starlet Romeo Lavia suffered a fresh injury setback ahead of Sunday's game at Wolves