Monaco, the only team other than PSG to have won Ligue 1 since Montpellier's shock triumph in 2012, eased to a fourth straight victory.
The Brazil centre-back had already been ruled out of the Champions League quarter-final with Bayern Munich later in the day.
PSG are second at the season's halfway stage, a point behind the leaders Lyon and ahead on goal difference of third-placed Lille, who triumphed 1-0 at Nimes.
Cavani is not travelling with the United squad to Paris as he was not deemed fit enough to play after seven months out of action.
Ligue 1: Neymar in PSG squad for Marseille clash after beating COVID-19; Kylian Mbappé, Marquinhos still out
PSG coach Thomas Tuchel is not sure whether Neymar, winger Angel Di Maria, goalkeeper Keylor Navas or midfielder Leandro Paredes will start the game at Parc des Princes.
Mauro Icardi's four-year deal with PSG leaves club's record scorer Edinson Cavani's future uncertain
Icardi joined PSG on a season's loan and had impressed with 20 goals in 31 games when the league season was stopped because of the coronavirus pandemic
Ligue 1 champions Paris Saint-Germain seal transfer of striker Mauro Icardi from Inter Milan on four-year deal
French champions Paris Saint-Germain have signed striker Mauro Icardi from Inter Milan on a four-year deal.
Champions League: PSG coach Thomas Tuchel 'really surprised' to see video of players at party after Borussia Dortmund defeat
Neymar and Kylian Mbappe were among those attending a late party to celebrate the birthdays of Mauro Icardi, Edinson Cavani and Angel Di Maria
Ligue 1: League-leaders Paris Saint-Germain beat Nantes to move 15 points clear; Monaco scrape to first win under Robert Moreno
France striker Kylian Mbappe, who angrily snubbed Paris Saint-Germain coach Thomas Tuchel after being substituted in Saturday's 5-0 home win against Montpellier, set up the first goal in the 29th
Coupe de la Ligue: Mauro Icardi continues goalscoring form as Paris Saint-Germain thrash 10-man Saint Etienne
Argentine Icardi, on loan from Inter Milan, scored either side of the interval with Neymar, a Jessy Moulin own goal and a Kylian Mbappe effort adding to the woes of Les Verts, who were reduced to 10 men when Wesley Fofana was sent off after half an hour
Kylian Mbappe celebrated turning 21 with a silvery-looking haircut and two more clinical finishes as league leaders Paris Saint-Germain beat struggling Amiens 4-1
Ligue 1: Neymar, Kylian Mbappe, Mauro Icardi score as PSG recover from goal down to beat Montpellier
Neymar, Kylian Mbappe and Mauro Icardi used their individual brilliance to compensate for a poor team performance as Paris Saint-Germain recovered to beat Montpellier 3-1
PSG moved to 33 points ahead of second-placed Olympique Marseille, who visit second-bottom Toulouse on Sunday, while Lille are seventh on 19.
Mauro Icardi came off the bench to score a late winner as Paris Saint-Germain extended their Ligue 1 lead to nine points despite another unconvincing performance in a 2-1 victory at Brest on Saturday.
Ligue 1: Paris Saint-Germain coach Thomas Tuchel hints at Edinson Cavani returning to starting line-up for clash against Brest
Cavani has been absent from the French champions' starting line-up thanks to a combination of the persistent injury and the hot form of new arrival Mauro Icardi.
Champions League: Juventus, PSG and Bayern Munich through to knockout stages; Manchester City made to wait by Atalanta
Premier League champions Man City were made to wait after Atalanta's second-half fightback at the San Siro resulted in a 1-1 draw
Ligue 1: Mauro Icardi, Kylian Mbappe score twice as Paris Saint-Germain outclass old rivals Marseille
Mauro Icardi and Kylian Mbappe both scored twice as Paris Saint-Germain demolished their old rivals Marseille 4-0 on Sunday in a game that further laid bare the gulf that exists between the sides and allowed the reigning champions to extend their lead at the top of Ligue 1.
Champions League: Raheem Sterling, Kylian Mbappe score hat-tricks as Manchester City, PSG record big wins; Tottenham crush Red Star Belgrade
Raheem Sterling and Kylian Mbappe both scored second-half hat-tricks in UEFA Champions League action on Tuesday as Manchester City, Paris Saint-Germain and Tottenham Hotspur all recorded big victories.
Ligue 1: Angel Di Maria's brace, Kylian Mbappe's late goal anchor PSG's 4-1 win over Nice at Allianz Riviera
Nantes could trim PSG's lead back to two points on Saturday when they head to bottom side Metz, while Rudi Garcia begins his reign as Lyon manager against lowly Dijon
Former Inter Milan captain Icardi arrived in the French capital on loan this season and after recovering from injury, has scored two goals in the Champions League and Ligue 1