Captain John Terry took part in training at Chelsea's Surrey training base on Monday ahead of the club's trip to France for the Champions League last 16 first leg with Paris St Germain.
The 35-year-old went off with a hamstring injury towards the end of the first half of Saturday's 5-1 Premier League win over Newcastle.
Terry underwent a scan on Sunday but the Blues declined to reveal the results. His next appearance will be his 700th for Chelsea.
Interim boss Guus Hiddink may declare if Terry is fit or not in his pre-match media conference at Parc des Princes on Monday, or he may choose to give Terry as much time as possible to prove his fitness.
Brazil playmaker Oscar, who missed Chelsea's match with the Magpies, also took part in training.
A story on Chelsea's official website read: "John Terry and Oscar were both able to take part in the final training session before the Champions League Round of 16 first-leg match in Paris tomorrow (Tuesday).
"The Chelsea captain was withdrawn during the first half of Saturday's win over Newcastle due to what Guus Hiddink reported afterwards might be a slight muscular problem with his hamstring. Oscar missed the game with a minor calf injury."
Nemanja Matic is suspended for the match and Kurt Zouma (knee) is absent until the end of the season.
If Terry does not make it, Branislav Ivanovic is likely to switch from right-back to the centre of defence, with Cesar Azpilicueta on the right flank and Baba Rahman at left-back.
Chelsea face a pivotal week, with Manchester City visiting Stamford Bridge in the FA Cup fifth round on Sunday.