Yvan Muller scored his first World Touring Car Championship victory for Citroen at a damp Paul Ricard.
Reigning WTCC champion Muller inherited pole position following the demotion of provisional pole-winner Sebastien Loeb and second-fastest qualifier Jose Maria Lopez due to problems with their automatic fuel cut-off systems in post-qualifying technical checks.
Loeb and Lopez's misfortune was offset by the Citroen's performance advantage.
Cheered on by a partisan home crowd, Loeb recovered to second position at the chequered flag, some 12.7 seconds behind Muller.
Lopez lost time in a minor off-track moment at Turn 1 on the opening lap, plus door-banging antics with Tiago Monteiro, and was further delayed behind a stubborn Lada Granta driven by an inspired Rob Huff.
The Argentinean would have to settle for fourth behind the factory Honda of Gabriele Tarquini, who was contesting his first race of 2014 - after last weekend's Marrakech practice crash - and 200th WTCC start.
From the outside of the front-row, Tarquini had made a perfect start to lead Zengo Honda driver Norbert Michelisz into Turn 1, while Muller struggled both to see the start lights and with excess wheelspin.
"It was one of my worst starts," said Muller, "I was having to crouch down to see the lights."
The Frenchman outbraked Michelisz into the final corner on lap one to recover to second place and grabbed the lead from Tarquini on the following tour.
Watch Ricard highlights videos on the AUTOSPORT WTCC page
Loeb's progress through the field underlined the nine-time World Rally champion's racecraft on the circuit. Up to seventh on lap one and sixth on lap two, Loeb's ascent appeared relatively effortless.
Struggling with a half-wet/half-dry set-up and gearshift problems, Tarquini nevertheless proved Loeb's toughest opponent. The ex-Formula 1 driver fended off the Citroen for four laps, but was finally passed at the Chicane Nord on the Mistral Straight two laps from home.
The battle for fifth, disputed by Michelisz, Huff and Campos Chevrolet driver Hugo Valente, generated much excitement in the closing stages.
Michelisz had clouted Lopez during the charging Citroen's passing manoeuvre, and would slip down the order on the final two laps.
On the penultimate lap, Valente produced a huge slide to avoid crashing into Huff in an aborted passing attempt.
Former WTCC champion Huff immediately responded by putting distance between himself and Valente; attacking Michelisz and stealing fifth around the outside of Virage de Bendor.
Valente would also pass the ailing Michelisz, and stole sixth position on the last lap.
Results - 16 laps:
Pos Driver Team/Car Time/Gap
1. Yvan Muller Citroen 27m58.347s
2. Sebastien Loeb Citroen +12.727s
3. Gabriele Tarquini Honda +15.026s
4. Jose Maria Lopez Citroen +18.663s
5. Rob Huff Lada +31.393s
6. Hugo Valente Campos Chevrolet +34.415s
7. Norbert Michelisz Zengo Honda +34.896s
8. Tiago Monteiro Honda +37.918s
9. Tom Chilton ROAL Chevrolet +41.014s
10. James Thompson Lada +45.739s
11. Gianni Morbidelli Munnich Chevrolet +48.720s
12. Rene Munnich Munnich Chevrolet +49.234s
13. Mehdi Bennani Proteam Honda +57.136s
14. Dusan Borkovic Campos Chevrolet +1m02.522s
15. Mikhail Kozlovskiy Lada +1m05.813s
16. Franz Engstler Engstler BMW +1m46.587s*
17. Pasquale di Sabatino Engstler BMW +1 lap*
18. John Filippi Campos SEAT +1 lap*