Lyon is looking for a record-tying fourth straight title, a feat previously achieved by Saint-Etienne and Marseille.
Monaco had the better opportunities, but only broke through after Michael Essien was sent off in the 64th minute.
Defender Julien Rodriguez scored in the 83rd minute against a Lyon side reduced to 10 men, but Clement, a late addition to the squad because of an injury, met Juninho's curling 94th-minute free kick with a perfect header.
Monaco began brightly and in the fifth minute Mohamed Kallon tested goalkeeper Gregory Coupet with a shot from the edge of the penalty area.
Brazilian defender Maicon, Monaco's best player on the night, burst into the area in the 15th minute but tried to beat Coupet inside his near post when he could have squared to the unmarked Javier Saviola, lurking two yards from the goal.
Midway through the first half, Coupet's brilliant one-handed save stopped Maicon's swerving free kick.
In the 34th, Togo striker Emmanuel Adebayor sprinted down the middle and beat Coupet, only to have Brazilian defender Cris clear the ball away.
Lyon continued to struggle after halftime, with Cris and Eric Abidal forced to concede free kicks just outside the area.
In the 62nd minute, Essien's late tackle on Kallon prompted an outbreak of shoving among the players.
Two minutes later, tempers flared again when Essien elbowed Kallon and was sent off by referee Pascal Garibian. It was Lyon's first red card of the season.
Furious, Essien pushed Garibian and had to be dragged away by midfield partner Mahamadou Diarra.
Monaco's goal came when Maicon crossed into the penalty area and Rodriguez athletically half-volleyed the ball past Coupet and into the bottom-right corner.
It was his first goal for Monaco in 116 league matches.
Eleven-time Ukraine league champion Dynamo Kiev could come under scrutiny as part of the new Ukrainian government's review of past privatizations, a top government official said Friday, drawing an angry response from the club's president.
Deputy Prime Minister Mykola Tomenko said he would not rule out that Dynamo's ownership would be examined as part of a government effort to contest privatizations conducted illegally during the 10-year presidency of Leonid Kuchma, which ended last month.
Dynamo's president, Ihor Surkis, called Tomenko's statement "incompetent'" and said there were no legal grounds for questioning Dynamo.
RSS