De la Rosa: McLaren must keep improving

In 2007, Briton Lewis Hamilton lost the title in the final race, by a single point, despite having had a 17-point gap over eventual winner Kimi Raikkonen with just two races remaining.

Hamilton has again moved into the championship lead thanks to victory in the Monaco Grand Prix last weekend.

De la Rosa reckons consistency will be key in the title fight, and believes that the British squad cannot afford to relax and must keep improving.

"Hamilton is very confident and if he fulfills his promise of scoring 15 consecutive podiums, he may win the title," de la Rosa told reporters during the opening of Madrid's motor show.

"We have won two races out of six and we have been closer to Ferrari on the tracks where they beat us by much in 2007, but we must keep on improving the car because the championship is very long. We already lost it by one point last year."

The Spanish driver admitted he is missing Fernando Alonso this season, after the two-time champion left McLaren to return to Renault.

Alonso is now struggling to fight near the top and has scored just nine points so far this season.

Despite that, de la Rosa praised his compatriot, and he reckons Alonso is actually flattering Renault.

"Fernando is getting the R28 in the top ten," he said. "The car isn't there. If they progress a lot with the suspensions he might get a podium. I wish he does. I see him very calm but there's nothing worse than having a car that's not competitive.

"Of course you feel it when you don't have a two-time world champion. And I personally feel it more because I always had a good relationship with him, but there's no point in looking back and last year seems very far to me. I miss him but I'm happy about the way the team is working."