The French champions are 2-1 down from the first leg and need to net at least twice at the Etihad Stadium as a result.
Their hopes of a comeback were hit last week with news of striker Mbappe suffering an injury, and his manager says it will be touch and go as to whether he can include the World Cup-winner.
“With Kylian, we will make a decision on his fitness tomorrow,” Pochettino said in his press conference.
“He is going to start the individual training sessions and see if he can be with the team in the end.
“Yes I am worried for him – we want all the players fit and available. We are going to see in the coming hours if he will be available.”
If Mbappe cannot make the squad, Pochettino still expects that PSG will be able to progress to the final, pointing to others needing to step up and provide the moments which matter.
“We have a big squad – all the players can do the job. If Kylian is not available, the team has tools and the quality to try and win.”
Midfielder Marco Verratti is clearly hoping his team-mate will be fit, noting that he is one of the players capable of turning the tie in PSG’s favour.
“We have to believe in ourselves. There are going to be 11 warriors out there battling to win every ball. We are playing perhaps the best team in the world,” he said.
“Sometimes all it takes is a little stroke of genius from Neymar or Mbappe to change the game.”
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