Rossi had previously clocked a new pole record which set him apart at the top of the time sheets for the majority of the session, but Biaggi gradually picked up his pace and moved up to second spot in the latter parts of the session.  The Yamaha rider was on a fast lap when the clouds that have hung over the Valencia track throughout the day finally burst, but he bravely continued on the limit to take pole position with a time of 1'34.496.

"I worked hard in practice, mainly on setting the bike up for the race," said Biaggi. "Rossi's bike is the strongest here, he is very fast on the entry and exits of the corners but I think I did a good job. Halfway through that last lap I saw rain on my screen but I just had to keep going. When I saw my time I thought it would put me on the front row so to be on pole is a nice surprise."

Honda's Valentino Rossi was powerless to react as water bounced down on the asphalt, his frustration complete when the rain stopped almost immediately after the chequered flag was waved.

"We had just fitted my second soft rear slick when the rain came, but maybe I couldn't have got pole anyway. We did a lot of work today, changing various settings and working on our race tyres. Then we fitted my first soft rear and got provisional pole, before going back to working on our race set-up. Seriously though, I can't say I don't care about pole position, but the main thing is to have a good race set-up which will allow me to do good times all-race long."

Nakano made a slight impression on the Italian dominance witnessed this season in the 500 class, qualifying in third place ahead of Capirossi.

"That was a difficult session because one of my bikes developed an electrical problem," said Capirossi. "Anyway, I'm happy because we have a good set-up for the race and that's what matters most."

McCoy was 5th quickest - "Our session was cut short by a couple of laps due to the rain, but to be honest I don't know if that was a good thing or a bad thing in terms of our final qualifying position. Concerning the bike's set up we seem to have found a compromise between grip and slide by using last years set up with a bit more drive. Our main problem now is tyre choice, as the temperature kept changing and we didn't get a chance to do much endurance testing."

Former World Champion Alex Crivillé (Repsol YPF Honda NSR500) was running third with 20 minutes to go but had slipped to sixth by the end of the session. The Spaniard is not downhearted, however. Lap times are so tantalisingly close here - with one second covering the fastest 12 men - that any of the top 12 could be in the running for victory, so long as they get a good start.

"Everyone's lap times are so close, it's impressive," said Crivillé. "I was third at one stage, returned to the pits to change tyres, and before I could blink I was down to sixth. The slightest diversion can throw you from the front row to the third row."

Team-mate Tohru Ukawa (Repsol YPF Honda NSR500) and Capirossi's team partner Alex Barros (West Honda Pons NSR500) fill the middle of the third row in tenth and 11th. Both had also been in the running for a front-row start, Barros second yesterday and Ukawa fifth, but couldn't quite raise the pace as required today.

Today's times were much faster, with Biaggi improving his pace by 1.2 seconds. Michelin technicians attributed the improvement to better grip. "The torrential rain we had here on Wednesday night washed dust on to the track, so it was dirty yesterday," said Michelin's Jacques Morelli. "The surface was cleaner today, so there was more grip."

Ukawa, who scored his first 500 front-row start at Estoril two weeks ago, had this to say: "It's a shame, a good grid position slipped through our fingers. But I think I can run the race pace, which should be around 1m 35.5s or low 1m 36s. We have a good tyre choice for the race, so long as the pace isn't too fast."

Barros said: "I'm not happy I couldn't go faster but I think I can run the race pace, and so long as I can get a good start I can be in the leading group. I'm a little disappointed after going so well yesterday, but I'll do my best to get a good result tomorrow."

Fonsi Nieto took his first ever pole position from a surprise packed 250 session which saw fellow Spaniard and Valencia Circuit Aspar Team colleague Alex Debon qualify in second position. The Spanish pair, who both ride Aprilia machinery, delighted the home crowd and the Italian factory, who dominate the front row with Locatelli and Harada in third in fourth respectively. Harada's premonition that the Aprilia was more suited to the circuit than the Honda was realised as Championship leader Katoh struggled to keep pace with the top riders and was forced to settle for a second row start. Katoh will line up in fifth spot ahead of Melandri, Matsudo and McWilliams. Rain which fell early in the session had dried up by the halfway mark and the majority of riders were able to improve their provisional times from yesterday.

There was further cheer for the Spanish supporters in the 125 class as Toni Elias set a new best pole under pressure from Sanna, Cecchinello and Sabbatani. A hectic finale to an intensely contested session completely reshuffled the grid in the dying seconds, and when the dust settled the Italian trio found themselves alongside Elias on the front row in second, third and fourth place respectively. Poggiali, who lies just 13 points behind Championship leader Elias in the current rider standings, tried in vain to improve his provisional qualifying time, and he will now start from the third row of the grid in twelfth position.