LET'S KEEP IT CLEAN

After pulling the wraps off McLaren's new car, Formula One rivals Lewis Hamilton and

Jenson Button used their first public appearance as teammates on Friday to pledge a clean fight for the championship.

Becoming the first F1 team to start the season with the last two champions is a gamble for McLaren, which is all too aware of the potential pitfalls.

Race fans in Bahrain have a special interest in the success of the team as Mumtalakat, the kingdom's investment arm established as an independent holding company for the government's non-oil and gas assets, has a 30 per cent stake in the business.

The team's 2007 season was blighted by intrigue and infighting as 2006 champion Fernando Alonso - in his one and only year with McLaren - complained that debutant

Hamilton was the favoured driver.

But the 25-year-old Hamilton, who claimed the 2008 title, believes he has learned from that fraught debut season in F1 and is ready for the challenge from Button, the 2009

champion who has defected from Brawn GP.

"I think we can work together more," Hamilton said, standing next to Button. "In 2007, perhaps in some cases, we (Hamilton and Alonso) didn't work together well enough

and we didn't work together for the team. I think we both understand we need to work together to push the team forward.

"Of course, we want to beat each other, to get to the end of the year having won the constructors' championship and one of us having won the drivers' championship. I think we both understand that."

McLaren team principal Martin Whitmarsh insists there will be no favoritism.

"We've got two drivers who are very honest and very open," Whitmarsh said. "They both want to beat each other - I'd be worried if they didn't. But I think it's going to be clean, going to be open and it's going to be co-operative.

"Inevitably, if they are nip and tuck, and they are taking points from one another, if you're fighting a one-man team, then it does become difficult. But they are really super personalities, terrific assets, you can sense it."

It will be Button's MP4-25 car adorned with the No. 1, though, after finishing 46 points ahead of Hamilton.

"I go into the season excited about the new season, the most excited I've ever been ahead of a new season, but not looking to prove anything to anyone," the 30-year-old Button said. "I don't need to do that. I don't need to prove anything to myself because I am pretty happy with where I am in my life right now. I am in the best position I possibly could be.

"I have the experience of winning the world championship in 2009 which is a boost to your confidence. I've also gained a lot of experience, and as a person I've become a lot more confident than last season.

"You never know what to expect going into a new team, not knowing what the atmosphere will be. I've been pleasantly surprised."

Both Button and Hamilton are eager to forget the 2009 season - for very different reasons.

While Button doesn't want to dwell on ending his long wait for a first title, Hamilton had a difficult third season in an uncompetitive McLaren.

"After the last race you think about what you have achieved and it goes through your mind, the road to becoming world champion, but soon after that you start forgetting because you are already focused on 2010 and the new challenge," Button added. "We need to start forgetting about last year ... and start looking to the future."

Hamilton, who won the title in his second season in F1, is hoping the improvements in downforce and aero efficiency will allow him to challenge for the championship again this season.

"I'm sure it's going to handle completely differently to last year's car," Hamilton said. "I hope so."

Testing began this week, and each driver will have seven days in the car ahead of the season-opening race in Bahrain in March.