Chevrolet's Yvan Muller extended his lead at the head of the World Touring Car Championship drivers' standings after claiming his sixth victory of the season at Algarve circuit.
Starting alongside polesitter Gabriele Tarquini (Lukoil Racing), Muller enjoyed a strong getaway from the outside of the front row at the rolling start, taking the lead from Tarquini around the outside at Turn 1.
The Italian stayed in touch with Muller throughout, but contending with pressure from Muller's factory Chevrolet team-mate Rob Huff was unable to stage an overtaking attempt.
The order among the top four remained unchanged after the completion of the opening tour. Despite the failure of a passing manoeuvre to materialise, the leaders proved closely matched and were separated by less than a second at the chequered flag.
After being demoted into Turn 1, Norbert Michelisz - who qualified third - did well to hang on to the bumper of Huff's Cruze in the early laps. The Zengo Motorsport racer gradually dropped back and completed a relatively lonely run to fourth.
Following a difficult final qualifying session, in which he suffered an large oversteer moment on his hot lap, the third factory Cruze of Alain Menu provided some excitement as the Swiss progressed up the order from a ninth place grid position.
Menu is under investigation however for a first-lap incident in which he tapped Tarquini's team-mate Aleksei Dudukalo into a half-spin.
While Menu continued, Dudukalo later ran wide at Turn 11 and rejoined into the path of the unfortunate Gabor Weber (Zengo Motorsport), causing the Hungarian's retirement.
On lap four, Menu overtook local hero Tiago Monteiro (Tuenti SEAT) into Turn 2, and two laps later slipstreamed the ROAL BMW of Tom Coronel for fifth across the start-finish straight.
Coronel completed the top six ahead of Monteiro and a strong showing from the second ROAL entry of Italian Superstars champion Alberto Cerqui.
Results - 11 laps: Pos Driver Team/Car Time/Gap 1. Yvan Muller Chevrolet 21m20.620s 2. Gabriele Tarquini Lukoil SEAT + 0.336s 3. Rob Huff Chevrolet + 0.951s 4. Norbert Michelisz Zengo BMW + 6.699s 5. Alain Menu Chevrolet + 13.669s 6. Tom Coronel ROAL BMW + 17.053s 7. Tiago Monteiro SUNRED SEAT + 20.172s 8. Alberto Cerqui ROAL BMW + 20.422s 9. Pepe Oriola SUNRED SEAT + 21.134s 10. Alex MacDowall bamboo Chevrolet + 21.723s 11. Stefano D'Aste Wiechers BMW + 22.453s 12. Franz Engstler Engstler BMW + 26.142s 13. Darryl O'Young Special Tuning SEAT + 29.066s 14. Tom Boardman Special Tuning SEAT + 29.813s 15. Pasquale di Sabatino bamboo Chevrolet + 34.752s 16. Tom Chilton Arena Ford + 42.163s Retirements: James Thompson TMS Lada 10 laps Charles Ng Engstler BMW 9 laps James Nash Arena Ford 7 laps Mehdi Bennani Proteam BMW 7 laps Gabor Weber Zengo BMW 4 laps Aleksei Dudukalo Lukoil SEAT 2 laps