Neymar was ruled out for up to four weeks after suffering an adductor injury in PSG's Coupe de France clash with Caen on Thursday (AEDT).
He will miss Wednesday's (AEDT) trip to Camp Nou to face his former club Barcelona in the first leg of the UEFA Champions League Round of 16 clash.
The timeline also puts him in doubt for the return leg at Parc des Princes on 11 March (AEDT).
Neymar spoke of his immense sadness in an Instagram following news of his injury.
Asked about the Brazil forward ahead of the Ligue 1 clash with Nice, PSG boss Pochettino said: "We have been speaking since the injury happened and, with the tests that he had yesterday, he has made his sadness and pain public.
"We are all going to help him get back as quickly as possible. And also help him recover in terms of his emotional state because it has been a tough blow for him.
"He is a tough guy and he is very mature. We have got to know him here to see what a great person he is, not just an athlete, but an extraordinary person who builds good relationships and is very likeable."
Pochettino brushed off talk of him taking an unnecessary risk by playing Neymar against Caen with Barca on the horizon.
"We are here to manage a squad of players and we make decisions that we think are for the best," Pochettino explained.
"We make decisions together and try to apply that all the time. A player got injured and that can happen. That can happen in the Coupe de France, in training, in the league, in the [UEFA] Champions League.
"It is a shame that he got injured, but these things happen in football.
"We cannot look back. We have key players injured and we have to look for solutions, while also knowing that we have a squad that can still handle that and play well in these fixtures.
"Whether it is Ligue 1 or the Champions League, I have total confidence in the squad, and they are PSG players for a reason. So we are going to try to go into every game to win without any excuses."