Cavani, now PSG's main striker after Zlatan Ibrahimovic's departure to Manchester United, wasted half a dozen clear cut chances and the crowd lost patience with him and jeered him off the pitch at the end.
Instead, it was left to Brazilian Lucas Moura to open the scoring for the title holders with a thumping finish seven minutes into the second half.
The hosts then endured some nervous moments with goalkeeper Kevin Trapp making good saves from Renaud Cohade and Mevlut Erding before Lavyin Kurzawa headed in from a corner to extend their lead in the 67th minute.
An own goal in added time by Jonathan Rivierez, who deflected Marco Verratti's shot into the net, completed the win for Unai Emery's side, who have six points from their opening two games alongside Olympique Lyonnais and Nice.
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(Writing by Brian Homewood; Editing by Rex Gowar)
