The reigning French champions are already without the world's most expensive player Neymar, who is battling for fitness after a re-occurrence of a foot injury which plagued him last season.
"The club will issue a statement later during the day".
Cavani put PSG ahead from the penalty spot in the 42nd minute when, moments later, he walked off before the halftime whistle.
Neymar has been ruled out until April with a metatarsal injury and striker Edinson Cavani, who has scored 22 goals this season, is a huge doubt after PSG confirmed that he sustained an injury to his right thigh against Bordeaux.
"We await the final session and I hope that they will both be able to play versus Bordeaux". But when Edi comes out in the 43rd minute, I'm scared, it's clear.
When questioned about Cavani's chances of playing at Old Trafford, Tuchel replied: "A little hope, very small, but yes, we still have hope". We are no longer looking at Plan B, but Plan D!
Sanchez says PSG will provide a "big test" but is confident United will progress, especially if they win the home leg without conceding.
"I can't think about so many different plans in advance. They need to know how to control and handle the pressure, but without two or three of them, it is up to us to come up with solutions".
The was some good news for PSG as midfielder Marco Verratti returned to the line-up after recovering from an ankle injury.
However, with the Portuguese's sacking, United have been on the uptrend under Ole Gunnar Solskjaer and they are now unbeaten in 11 successive games which includes 10 wins.
United scraped through the Champions League group stage under former manager Jose Mourinho, but are unbeaten under caretaker boss Ole Gunnar Solskjaer.