Mauricio Pochettino wants "special player" Kylian Mbappe to enjoy himself on the pitch, which could help him to regain his best form.
Mbappe has 12 goals in 14 Ligue 1 matches this season but has not been at the peak of his powers amid concerns over burnout.
Pochettino said the 22-year-old needed to improve after Paris Saint-Germain were held to a 1-1 draw at Saint-Etienne in the new head coach's first game in charge on Wednesday.
Ahead of facing Brest in his first home game since replacing Thomas Tuchel on Saturday, Pochettino was asked if forward Mbappe still seemed tired.
"It is a question about a special player," Pochettino said of Mbappe, who is in negotiations to renew his contract beyond 2022 amid speculation he could move on.
"He came back in good shape after the break, with a very good state of mind.
"He is the top scorer in the championship. We hope that he will have fun and find the performance of which he is capable."
Returning to Parc des Princes, where he played from 2001 until 2003, is an occasion former Tottenham boss Pochettino – who will again be without star forward Neymar - is looking forward to.
"It's going to be a special night and a joy, yes, 20 years after wearing this jersey," he said.
"Unfortunately there will be no supporters, it's a shame and that will be missing.
"In any case, we talked about it among ourselves and with our families: we have the impression that we have been here for a year, whereas it's only been five or six days!"
With one game to go until Ligue 1 reaches its halfway stage, champions PSG are three points behind leaders Lyon.