Williams continues to show a strong pace at Barcelona, even if the only yardstick by which the Grover team can be measured is Spyker.

Today, both Nico Rosberg and Alex Wurz (right) posted their best times of the year at the Spanish track, narrowly (0.050s) missing out on going quickest overall.

"Today Nico and Alex swapped roles," revealed Dickie Sanford, "with Nico carrying out mapping and set-up tests, while Alex spent the day doing long runs and completed a race distance.

"Kazuki Nakajima will join Alex tomorrow for our last day of preparation work prior to the first race in Australia," he added.

Spyker is also making progress, with both Christijan albers and Adrian Sutil improving on their previous best times as the Dutch team continued to work on optimising set-up and collecting tyre data in preparation for next month's Australian Grand Prix.

In the afternoon both drivers conducted race simulations. However, while Sutil completed a full race distance, Albers' running was however limited by a minor mechanical problem.

"We had a reasonably productive day," said Mike Gascoyne, "working on the basic set-up and building up speed over a race distance. Adrian had no issues during the day, however Christijan's car developed a hydraulic leak that cut his race run short. It's not a major issue though and we should be back out tomorrow. This morning was a bit cooler and we had some problems trying to get the tyres to work, but we've got a handle on how to better the situation."

"I think we did OK," said Albers, "we're pushing flat out to get some more performance from the car and the tyres. We still need to get some higher temperatures in the tyres so we can make some big progress in the set-up. We have already made some steps though and tomorrow we'll be continuing the same programme - it's full on now."

"It was difficult at times to find a good balance," admitted Sutil. "We did some qualifying work and concentrated especially on longer runs and a race simulation in the afternoon. I feel I'm getting closer to the limit now and improving myself as well as the car."

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