Mateo Kovacic is available for Chelsea boss Graham Potter.
Kovacic missed Sunday's 2-0 defeat at Tottenham through illness, as pressure intensified on head coach Potter and the Blues.
But the Croat has returned to training and is available for Saturday's Premier League game at home against Leeds, reports the London Evening Standard.
Chelsea then play Dortmund in the Champions League at Stamford Bridge next week, trailing 1-0 from the first leg of their last-16 tie last month.
N'Golo Kante and Christian Pulisic are also closing in on a return.
There is a growing feeling that the next two games could be make or break for Potter, though he retains the support of Chelsea's owners for now.