The World Cup winner was initially ruled out for three weeks, and Thomas Tuchel was not optimistic of a prized asset making a full recovery in time for the trip to Lisbon before a friendly win against Sochaux on Wednesday.
"The deadline is short, super short," the PSG boss told reporters. "We spoke with the doctor today and we decided to meet again on Saturday to see what phase he is in and if it is possible that he is on the bench against Atalanta.
"But I do not expect too much."
Tuchel also revealed that Italian midfielder Marco Verratti's participation in Europe was in doubt, as he missed the clash with Sochaux due to a calf injury suffered in training.
And despite Verratti's name initially being listed as part of the 28-man squad travelling to Faro on Saturday, sources have confirmed to Goal that the Italian didn't actually join the squad on the flight.
It is unclear if he'll arrive separately later although he is already ruled out of the clash with Atalanta.
Meanwhile, Neymar, Marquinhos, Angel Di Maria, Thiago Silva, Mauro Icardi, Thilo Kehrer and Presnel Kimpembe have all been restored to the squad after being rested for the midweek warm-up fixture, but Layvin Kurzawa will sit out the game due to a thigh issue.
PSG will be aiming to reach the semi-finals of the Champions League for the first time since 1994-95, with the winners of the last-eight encounter set to be rewarded with a tie against either Atletico Madrid or RB Leipzig.
Paris Saint-Germain's travelling Champions League squad in full
Goalkeepers: Keylor Navas, Sergio Rico, Marcin Bulka, Garissone Innocent
Defenders: Thiago Silva, Marquinhos, Presnel Kimpembe, Thilo Kehrer, Layvin Kurzawa, Colin Dagba, Juan Bernat, Mitchel Bakker, Abdou Diallo, Loic Mbe Soh, Timothee Pembele
Midfielders: Leandro Paredes, Idrissa Gueye, Julian Draxler, Ander Herrera, Kays Ruiz-Atil
Forwards: Pablo Sarabia, Eric Maxim Choupo-Moting, Neymar, Kylian Mbappe, Angel Di Maria, Mauro Icardi, Arnaud Kalimuendo