Returning Odsonne Edouard could make Celtic’s flight to France today.
But Hoops boss Neil Lennon has revealed defender Christopher Jullien has been sent to Germany for specialist back treatment as he faces an extended period out.
Lennon also confessed James Forrest may be out longer than anticipated with a delay in the healing of a fractured ankle.
Striker Edouard is slowly building back up to full speed after he tested positive for coronavirus two weeks ago.
He is ahead of Nir Bitton, who also tested positive in the international break, but Lennon hopes both will make the squad for Lille.
He said: “Odsonne has trained for the last few days and Nir also trained, although his sessions are a little bit modified.
“We’ll see how they are on Wednesday, but I’m hoping they will both be fit to travel.
“It’s a welcome boost having Odsonne back, but I’m not expecting him to hit the ground running. The same goes for Nir.
“We’re getting a few bodies back now so the squad is starting to look stronger again.”
It’s a different tale with Jullien and Forrest.
Lennon said: “He [Jullien] is over in Germany having intensive treatment on his back, but we’re looking at a few weeks from now before he returns to training.
“James is seeing a specialist about his ankle.
“It hasn’t healed as we’d hoped and he may need more time in a protective boot or it may need something else entirely. We’ll know more in the next day or two.”