Raikkonen and Alonso warm up for new duel

Both Raikkonen and Alonso slithered off track at times as they tested the limits, neither of them doing any damage. Conditions were relatively cool as low cloud persisted throughout the day and there was a high level of moisture in the air. Lap times were, for the first time this season, considerably quicker than last year's.

According to Bridgestone and Michelin, wear on the circuit's bitumen has exposed more of the underlying asphalt, improving the grip. That, in turn, has raised concern that tomorrow's China Grand Prix will be even more gruelling than last year's event.

"The car was quite hard to drive ," Alonso said, "but I think that is normal on the first day at this circuit. It was also very windy, which had an impact on the car balance in the high-speed corners. But we managed to test all the tyres, did some good laps and completed our long runs: the two types of tyre are quite close in performance, so we will have to work on the choice tonight. I think the circuit conditions will improve tomorrow, and as the grip levels increase then the car balance will improve too."

"A good start to the weekend, and let's hope it continues this way," Raikkonen said. "Everything has been working well, and the car feels really strong."

While Raikkonen lapped his McLaren in 1min 34.092sec, the Spaniard took his Renault round in 1:34.226. Juan Pablo Montoya and Rubens Barrichello were close to them with 1:34.541 and 1:34.618 respectively, while Giancarlo Fisichella pushed his Renault to 1:34.932 for the seventh fastest time.

Jenson Button was ninth, and relieved to be driving after a viral infection that he picked up on Wednesday night turned into a high fever yesterday morning. BAR-Honda's test driver, Anthony Davidson, was on standby, but Button rallied.

"We've completed all our planned running for today and achieved a lot of laps," Button said. "We suffered from low grip this morning but the grip level improved in the afternoon. Overall, the car feels better to drive than in the last two races."

The newly crowned GP2 champion, Nico Rosberg, was present yesterday. The 20-year-old son of Williams' 1982 world champion, Keke Rosberg, is the team's official test driver, but is expected to race alongside Mark Webber in the team next season.

"Am I ready? Yes, definitely, 110 per cent ready," Rosberg told the BBC. "At the beginning of the week Frank Williams said I will be one of the three drivers for 2006. So at the least I will be test driver next year and, hopefully, a race driver. It will be decided in the next week or two. I feel very much at home and want to be part of the team next year." Sources say the deal is already done.

The weekend sees the privateers Peter Sauber and Paul Stoddart making their final appearances as team owners. Formula One's commercial rights holder, Bernie Ecclestone, attended a farewell dinner for Sauber on Thursday night, and said of Stoddart: "We can't let him leave. We'll have to find a job for him, won't we?"

The FIA president, Max Mosley, is unlikely to agree with Ecclestone on that point. He and Stoddart clashed repeatedly and there are suggestions that before handing over the reins of Minardi to Red Bull on 1 November, Stoddart may have one last shot in his locker before Mosley stands for re-election on 28 October.