PSG cruise into League Cup quarters without rested Neymar
Pablo Sarabia, Eric Maxim Choupo-Moting, Kylian Mbappe and Angel Di-Maria scored for the record eight-time tournament winners inside the opening 48 minutes as Harisson Manzala responded for the hosts in the final edition of the competition.
PSG coach Thomas Tuchel chose to leave the world's most expensive player, who has suffered with injuries since the start of the season, in Paris as the German made eight changes from the side which hammered Saint-Etienne on Sunday.
Le Mans coach Richard Dezire handed the club's record goal-scorer Vincent Crehin a start after the striker came off the bench to grab the winner against Ligue 2's bottom side Orleans on Friday.
Last year's quarter-finalists began the brightest at the MMArena as Spain attacker Sarabia, starting just his third game of the season, opened the scoring after 21 minutes.
Choupo-Moting added a second on the 41-minute mark and Mbappe side-footed home a third less than 90 seconds later.
Di Maria hit a fourth three minutes into the second half as Le Mans' goalkeeper Pierre Patron fumbled the Argentina attacker's effort into his own goal.
DR Congo youth international Harisson Manzala claimed a consolation effort with 35 minutes to play by scoring for the first time this term.
Mbappe was substituted for Mauro Icardi on the 68-minute mark with Tuchel turning his focus to Saturday's Ligue 1 fixture against Amiens, a final game before a two-week winter break.
Elsewhere, Lyon, who are yet to win the trophy, hammered Toulouse 4-1 without Memphis Depay who has been ruled out for six months with a knee injury.