The 12 rounds/24 races calendar of the 2011 World Touring Car Championship concluded its first half with the Portuguese round at Porto. The second biggest city only next to the capital of the country, Lisbon, is well known around the world, as its historic area had been registered as a World Heritage Site in 1996. The old and historic city now has hosted the world hottest battles by touring cars.

After a one year absence, the Portuguese round came back to the downtown of Port, a street race track which was temporarily built by using public roads around the City Park. This was one of two street track races on the WTCC calendar this year, with the only other one being in the final round in Macau.

In this unique and challenging track, the factory Chevrolet drivers were really fast from the beginning of the race weekend. Starting with the special test session on Friday, they totally dominated the top slots of timing sheets throughout the free practice and qualifying sessions on Saturday and then the warm-up session on Sunday morning.

The situation never changed for the rest of weekend. After the rolling start for Race 1 - the championship's 11th race, it was just the monopoly of three blue liveried Chevrolet Cruzes. Keeping the order on the starting grids, they immediately formed the leading group by themselves and began to pull away from the other cars.

Soon after the start, in Turn 2, Gabriele Tarquini who started from the fourth grid tried to catch Robert Huff in third and there was a slight contact between them. But it didn't lead to a significant accident and it was the first and last opportunity for the rest of the field to undermine the Chevrolet's domination. In fact, the Italian lost the position to Tiago Monteiro in the same Sunred's SEAT, immediately after his attempt to attack Huff's Chevrolet.

The local star wasn't also able to push the three Chevrolets and the gap with Huff running in third extended to 3.485 seconds, after first three laps. Consequently, the leading blue cars had a quite peaceful race and finished in the order of Alan Menu, Yvan Muller and Huff. Thus, the first street track battle of the season ended with the Chevrolet's podium sweep.

In the YOKOHAMA Trophy class, Norbert Michelisz in a BMW 320TC started from the top slot of the class and was totally unopposed during the race which he finished in eighth overall to secure the class victory.

For the second race of the day, Stefano D'Aste sat on the pole position and two Chevrolet drivers, Muller and Huff, took the second and third grids. At the standing start for Race 2, the Italian BMW driver led the field when they entered into Turn 1 and the other leading cars followed him almost in the order of starting grids. Behind them, Robert Dahlgren's Volvo C30 stalled but the cars behind steered clear of the Swede's halted car safely, so the race was on.

At the end of opening lap, D'Aste had a 0.523 second gap with Muller. However, the two Chevrolets quickly got close to the leader from behind on Lap 2 and the Italian was narrowly fending off the Frenchman's pursuit when they entered to the third lap.

On the second half of Lap 3, Muller began to put heavy pressure on D'Aste by weaving his car just behind the Italian's BMW and then managed to overtake the leader from the inside of Turn 19. From then on, the Chevrolet driver started to pull away from D'Aste with an overwhelming pace.

Instead of following the new leader closely, D'Aste then lost his position to another Chevrolet driver, Huff, on Lap 4, before the BMW driver was given a drive through penalty for a jump start, which virtually put an end to his race for the YOKOHAMA Trophy class victory.

The battle for the overall win now became a duel between Muller and Huff, and it heated up in the closing stage of the race. The Briton snapped at his teammate's heels on Lap 9, with his head lights on to put some pressure on the leader, and they approached to the chicane side-by-side with Huff on the outside. But his attempt to overtake resulted in a slight contact in the tight chicane and he had to run wide.

While Huff skillfully caught his car and brought it back to racing line, Muller somehow momentarily lost his speed a bit and this allowed Huff to get ahead of the Frenchman. The race stewards judged the contact and position change as a normal racing accident, so they completed a couple of remaining laps in this order and Huff scored his sixth win of the season.

The YOKOHAMA Trophy was won by Michelisz again, as he started from the seventh grid and finished the race in remarkable fourth overall. Since his championship rival Kristian Poulsen ended the both race in lower positions, now Michelisz became the championship leader of the class.