Alonso mystified by lack of speed

Alonso had been expected to challenge for a top four position, as team-mate Jarno Trulli achieved, but he had to settle for a fourth row spot instead.

"I had a clean lap but, in the end, it wasn't particularly quick," said Alonso. "I didn't make any mistakes and I was relatively pleased with the car's handling. However, the lap time just wasn't there: we now have to take a long hard look at the data to understand where the problem is."

Pat Symonds, Renault's executive director of engineering, said that the car's braking system was the suspected root cause.

"Fernando had a problem with his car that seriously compromised his ability to qualify well," he said. "At the moment we are not sure what it is, but as he is 8kph slower on the straight, and because we have also seen a problem with the braking system, we will start looking there."