Chelsea are set to be without Hakim Ziyech against West Ham on Monday in the Premier League.
The 27-year-old has been out with a hamstring injury and returned to training with the rest of the squad on Friday ahead of the London derby.
"It is their first day back with the group today training at a decent level, so I will have to see how they are the next two or three days to see if they make West Ham."
But Simon Johnson of the Athletic reports that the London derby is expected to come 'too soon' for the Moroccan winger.
It is more likely that Ziyech will be fit enough to return on Boxing Day against Arsenal.