Gignac, who opened the scoring in the second minute in last week's 3-1 triumph at Guingamp, ran on to a deep pass from Rod Fanni and fired the ball past Evian goalkeeper Bertrand Laquait after 16 minutes.
Last year's runners-up Marseille needed goalkeeper Steve Mandanda to make a couple of fine saves before they doubled their lead in the 67th minute when new signing Dimitri Payet, who scored twice in Guingamp, provided a curling finish.
Olympique Lyon delivered a superb attacking performance to win 3-1 at Sochaux on Friday and are level with Marseille on six points at the top of the table.
Champions Paris St Germain, who drew 1-1 at Montpellier last week, entertain Ajaccio on Sunday when big-spending Monaco also host Montpellier.
- Sports & Recreation
- Dimitri Payet
- Steve Mandanda
- Bertrand Laquait