'Bit of a problem' at Yamaha.

An unexpected lack of grip has left Fiat Yamaha riders Valentino Rossi and Colin Edwards with 'a bit of problem' at the Spanish Grand Prix.

Rossi came into the event favourite for victory, having been fastest of all during recent testing at the same track and finishing a close second to Ducati's Casey Stoner - despite a clear top-speed deficit - at the Qatar season opener.

However, the seven-times world champion was left just eighth in first free practice, and could only to improve to sixth after Friday's second and final hour of track time.

"Today was quite difficult for us, compared to how we began in Qatar," admitted Rossi. "Unfortunately the situation with the tyre is not perfect, we don't have enough grip and the problem is made worse because the condition of the track isn't so good either. We have a lot less grip than we had at the test here so now we need to work more on the setting of the bike in order to improve the grip with the tyres we have.

"This morning the problem was a lot worse and we were quite worried after the first session, but we've worked very hard today and the situation this afternoon is a lot better. Anyway we're not that far away at the end of the day, only sixth, and all the riders are very close together so I don't think we need to worry yet," reassured Rossi. "It's clear that some of our rivals are very strong and it's going to be a hard battle, so we need to make the most of the time we have left. I hope that the track grip will improve tomorrow as more rubber is laid down and I hope it will also be a little bit warmer in the morning so we can work properly during free practice."

Having excelled during practice and qualifying at Qatar, only to struggle in the race, Edwards had predicted a return to the top this weekend - especially after finishing third in the pre-season test - but the Texan managed only ninth in both practice sessions, and confessed that the team has 'a bit of a problem'.

"We've definitely got a little bit of a problem to deal with and I can't say we're in the same shape we were in at this stage of the Qatar race," said Colin. "We know what tyre worked here at the test and the bike is basically the same, with a few improvements, but the conditions here today are pretty different and it seems things aren't quite working the way we expected.

"The main problem is that we can't get the rear to hold on and we're just sliding around a bit. It's disappointing because at the test here our grip and our speed through the corners was our best thing, but here it seems we've lost that a bit and we're not entirely sure why at the moment.

"We've tried quite a few different tyres but we couldn't find something that worked perfectly today. We're obviously restricted with our tyre choice because of the new rules, so now we're going to need to make some changes to the bike in order to get it to work with what we've got. The bike feels great and I'm happy with it, it's just a matter of grip. We've got a lot of ideas and we'll have a good chat about it tonight and start again in the morning. I am sure we'll be able to come up with something!" he concluded.

Despite their positions, the ultra-close lap times meant that Rossi was only 0.347secs from fastest man Carlos Checa with Edwards 0.488secs adrift.