Reigning F1 World Champion Jenson Button has sought to downplay his chances of making it back-to-back triumphs with McLaren-Mercedes in this weekend's 2010 Malaysian Grand Prix at Sepang, after struggling to find a satisfactory set-up for much of opening practice.

Having broken his McLaren duck at only his second attempt courtesy of a flawlessly composed and tactically astute performance Down Under in Melbourne last weekend, the next task for Button is to win again - to prove to his detractors that his Australian Grand Prix success was not a lucky fluke enabled by the majority of his rivals tripping over either themselves or each other on a day when the action well-and-truly returned to the top flight.

However, that second victory is unlikely to come in Kuala Lumpur, he cautions, after grappling with set-up issues during Friday practice that left the 30-year-old in fourth spot, just shy of four tenths of a second adrift of pace-setting team-mate Lewis Hamilton on the end-of-day timesheets.

Button ascended the top step of the podium in Malaysia this time last year after mastering torrential conditions to prevail in what was ultimately a significantly truncated grand prix - with not altogether dissimilar conditions anticipated again twelve months on - but even though he insists he now feels completely at home in his new team, the defending race-winner is not raising his hopes too high regarding the likelihood of McLaren successfully taking the fight to Red Bull Racing and Ferrari this weekend.

"It took me quite a while to get to grips with the car's set-up today," reported the Frome-born ace. "I wasn't satisfied with it at first - I didn't really get a balance that I was happy with - but towards the end of the session it started getting better. That was encouraging - it was nice to see that we made some improvements right at the end, because it was quite a way from what I wanted.

"This car takes a bit of time to get used to and understand, but I feel good in that area. There are still a few things we were are working on so it feels more like my own, but considering that the performance is reasonable. We're steadily getting there and it's starting to take shape. We don't know what the weather's supposed to do tomorrow, but we'll deal with it whatever it is!

"The atmosphere in the team is very good and I feel at home. Obviously a good result helps that, but even before Melbourne I felt at home and like I have been with the team a very long time. Last year it was different, because in Melbourne we did have the best car and then coming here we also felt we would have a good result.

"Winning with the best car or equal best car is an amazing feeling, because you have won the race but you needed to win as you never know what is going to be happening later in the year. When your car is not the quickest one out there - especially in qualifying - it does mean a bit more as you are doing better than expected of the car.

"The first two races we went to last year we thought we had good chance of winning, but this time I think it is more difficult to challenge for a win. I am not saying it is out of the question, but more difficult. We will see on Saturday - if our qualifying pace is good there is a good chance of doing well."

"Jenson struggled to find a satisfactory balance, particularly at the start of this afternoon's session," corroborated the Woking-based concern's team principal Martin Whitmarsh, "but he and his engineers worked well together to improve this deficit by the end of the afternoon. I'm positive that he'll make further progress overnight. While we're mindful that the unpredictable Malaysian weather may play a role in determining the outcome of tomorrow's grid, we're nonetheless pleased with the foundations we've laid today."