The Spanish forward suffered the problem late on in the game and was forced off after picking up a shoulder problem.
Willian scored the only goal of the game for the west London side as Chelsea FC kicked off their Europa League campaign with a solid victory in Greece.
Pedro’s injury was the only downside of an otherwise positive night for the west London side, however, Chelsea FC boss Sarri seems to be hopeful that the problem is not too serious.
Speaking at his post-match news conference, Sarri said: “It is a problem with his shoulder.
“I don’t know exactly the situation, I have only talked to the doctor for a few seconds and the doctor said probably it is not a very serious injury.”
Chelsea FC will now switch their attentions back towards Premier League affairs and their trip to London rivals West Ham United on Sunday afternoon.
The west London side have made a brilliant start to the new season under Sarri, winning all five of their opening Premier League games to leave them flying high at the top of the table.
Chelsea FC brought in Sarri as their new manager after opting to part company with Antonio Conte this summer.
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