Mendes has been booked twice in nine appearances in the competition this season, meaning he is one yellow card away from having to serve a one-match suspension.
The defender, to his credit, has managed to watch his step since the second of those bookings which came in the 2-1 home defeat by Bayern Munich in the fourth game from the league phase.
Mendes was rested for PSG’s 3-0 win over Metz at the weekend, but is expected to return to the starting line-up on Wednesday night as Luis Enrique’s side aim to qualify for the round of 16.
Should Mendes start and be shown a yellow card, he will be banned for PSG’s last-16 first leg showdown, should they beat Monaco.
As a result of finishing 11th in the league phase, PSG - if they overcome their Ligue 1 rivals - will face either Barcelona or Chelsea in the last-16.
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Yellow cards in the Champions League are not reset until after the quarter-final stage and Mendes, as things stand, is the only PSG player in immediate danger of a suspension.
Achraf Hakimi, Khvicha Kvaratskhelia and Warren Zaire-Emery are all on one yellow card, while Illia Zabarnyi and Lucas Hernandez have already served bans following red card offences in the league phase.
The holders came back to win from 2-0 down in the first leg last week.
Desire Doue - a first half replacement for the injured Ousmane Dembele - scored twice and Hakimi netted the other to secure a 3-2 lead for PSG to defend at the Parc des Princes.