Alonso remains cautious after practice

Both Alonso and title rival Michael Schumacher kept out of each other's way in the morning session, with Alonso watching and waiting from the pit wall as a string of test drivers kicked off what promises to be a crucial weekend for both men.

Alonso, winner in China last year on his way to becoming Formula One's youngest champion, habitually sits out the opening practice session to limit the mileage on an engine that must last for two races.

He has a new and more powerful unit in China after a failure at Monza three weeks ago.

In the afternoon, the Renault driver set the sixth quickest time, one place behind Schumacher.

"We had to adjust our programme a little bit because of the rain in the afternoon session, but we have a good baseline to work from with the car," said Alonso. "It felt comfortable to drive straight away, so while we need to fine-tune things overnight, I am quite happy at the moment.

"This is a track I always enjoy, especially with the good memories from the championship win last year, and even with the V8 engines and the other changes since 2005, it still felt very good to drive today.

"I think we need to be a bit cautious analysing the times, because the conditions today are quite different to what we expect for the race. So we will wait for tomorrow until we get a final judgement for the tyre performance, but so far the Michelins seem to be working well."

Teammate Giancarlo Fisichella was encouraged by his start despite finishing down in 10th position.

"This was a promising start for me today," said Fisichella. "We improved the car a little bit during the session, in spite of the changing conditions owing to the rain, and the performance felt good.

"I didn't put together a full clean lap, so the lap-time could have been better, but the car felt consistent straight away and the tyres seemed good as well. It is hard to be certain in the judgement so early in the weekend, but I have a good feeling so far."