Ruben Loftus-Cheek could be facing a lengthy spell on the sidelines after going off injured against Nottingham Forest.
The midfielder was clearly crestfallen as he left the pitch three minutes before half-time at Stamford Bridge, where Chelsea beat Nottingham Forest 2-0 in the FA Cup third round.
Loftus-Cheek is desperate to establish himself in the Blues first team but has struggled with a persistent back problem for some time.
And a recurrence of the injury wrecked another important chance for the player to impress.
Chelsea coach Carlo Cudicini, who spoke at a post-match press conference, suggested that Loftus-Cheek might now be out of action for some time in order for the problem to be addressed.
Asked if Loftus-Cheek’s back injury was the reason he was taken off, Cudicini said: “Yes it is. We are very sorry for him.”
The Italian added: “His impact in games he has played so far has been very good and even today I feel he was contributing very much, so it’s a pity.
“It’s something that is obviously affecting him and something maybe we need to look at to resolve.
“It’s been going on for a while and it’s something he might have to have some time out to look at.”
Alvaro Morata’s goals, both set up by Callum Hudson-Odoi, took Chelsea through.
Cudicini praised Hudson-Odoi and suggested the youngster had proved a point to boss Maurizio Sarri.