Cavani left the pitch on the stroke of half-time holding his thigh, just after opening scoring with a penalty in the 43rd minute.
Edinson Cavani will sit out the first leg of Paris Saint-Germain's Champions League encounter with Manchester United, French sports daily L'Equipe and the daily Parisien newspaper reported on Sunday, while club coach Thomas Tuchel described his participation as highly unlikely.
"Without Neymar and possibly Cavani and [Marco] Verratti, we will have to think of a Plan D", Tuchel said after Saturday's game at the Parc des Princes.
The Champions League last-16 tie is so deliciously hard to call that Blanc, a former United defender and PSG coach, looks nearly physically pained when pushed to pick a victor.
PSG are already without Neymar, who was ruled out with a foot injury, leaving the French side with only Kylian Mbappe as a world-class striking option.
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Carbery atoned for his first half error with a stunning break and pass to release Keith Earls for the defining score of the game. He said after the game: "It happens to him because he is who he is, that's going to happen.
"Honestly, I don't know if he will be here on Tuesday". Yes, it is worrying.
When questioned about Cavani's chances of playing at Old Trafford, Tuchel replied: "A little hope, very small, but yes, we still have hope".
"It'll be super hard [for him to play at Old Trafford]".
"[There is a] very small hope, but the first tests were not good".
"There are a lot of plans B. Without Ney, maybe without Marco, maybe without Edi". To play against this team, you need to be stronger, more solid, with a different attitude.
"Marco Verratti wants to play but he only played 60 minutes once", he said.