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.
European football matchday: Chelsea face second-tier Barnsley in FA Cup; Athletic Bilbao host Levante in Copa del Rey
Rennes travel to face first-division rival Angers and Saint-Etienne go to second-tier Sochaux in the French Cup’s remaining round of 64 games.
Ligue 1: Paris Saint-Germain held in 'disappointed' Mauricio Pochettino's first match, Lyon extend lead
PSG fell behind early on to Romain Hamouma's strike before Moise Kean levelled soon after, but laboured in the second half and failed to find a winner.
Lyon continued their fine form with a 3-0 win over Reims while Monaco beat Nimes by the same scoreline to also move within two points of PSG. Montpellier, meanwhile, edged out Lorient.
Forward Karl Toko Ekambi put the home side ahead in the 21st minute when he volleyed in Memphis Depay's brilliant cross from the left. Reims midfielder Moreto Cassama was sent off 10 minutes later for fouling Depay as he was running through on goal.
Aouar was initially called up last week as a replacement for Nabil Fekir but instead joins the World Cup winner on the sidelines after hurting his thigh during Lyon's 2-1 derby victory on Sunday.
Only around 1,000 spectators were present at the Stade Velodrome due to coronavirus restrictions.
Montpellier's defense kept Nice striker Kasper Dolberg quiet while veteran center half Daniel Congré took care of scoring duties with two in a 3-1 win.
At least 37 Ligue 1 players from 11 clubs have tested positive for COVID-19 in recent weeks.
Ligue 1: Bordeaux appoint veteran Jean-Louis Gasset as head coach after parting ways with Paulo Sousa
Gasset was assistant to Laurent Blanc when Bordeaux won the French top flight in 2009.
French Cup: Paris Saint-Germain beat Saint-Etienne to clinch title as Kylian Mbappe limps off with ankle injury
Neymar struck Paris Saint-Germain's opening goal from close range in the 14th after goalkeeper Jessy Moulin saved Mbappé's shot.
Saint-Etienne announced the death of Herbin on Tuesday, without giving a cause, and described him as a “mythical character of French football” who “embodied” the club
Ligue 1: Benjamin Andre's goal powers Lille to crucial win over Nantes; Lyon climb to fifth spot after beating Saint-Etienne
Benjamin André headed home the winner as Lille won 1-0 at Nantes on Sunday to boost its bid for third place in the French league and a Champions League qualifying berth next season.
Ligue 1: Edinson Cavani scores as PSG beat Lyon to restore 12-point lead atop league table; Montpellier defeat Saint-Etienne
PSG overcame another shaky performance in defense to beat Lyon 4-2 on Sunday and restore its 12-point lead over second-place Marseille
Ligue 1: Kasper Dolberg strikes twice in Nice's win over Lyon; second-placed Marseille falter as PSG increase lead to 12 points
The first league defeat for Lyon this year left both clubs on 32 points, far behind league leader Paris Saint-Germain
Kylian Mbappe scored twice as Paris Saint-Germain moved seven points clear at the top of the French league with a resounding 4-0 win at 10-man Saint-Etienne on Sunday.
Ligue 1: Marseille stay close to league leaders PSG with victory over Bordeaux; Stade Reims earn rare win Saint-Etienne
With its sixth consecutive league win, nine-time champion Marseille remained five points behind PSG, which has a game in hand.
Ligue 1: Robert Beric's last-minute strike guides Saint-Etienne to narrow win over Lyon; Nimes hold Lille to a draw
Lyon began the weekend in trouble of their own, languishing a disappointing 11th after a domestic six-match winless run but buoyed by a Champions League victory at RB Leipzig.
Former UEFA president Michel Platini free to return to football after 4-year ban but investigation continues
Former UEFA president Michel Platini is finally free to return to football next week when his four-year ban for ethics violations ends.