McLaren boss Martin Whitmarsh is backing Jenson Button to ease his way to the Formula One title in a steady rather than spectacular style.

Button heads to Japan this weekend knowing he can be crowned world champion if he finishes five points ahead of Brawn GP team-mate Rubens Barrichello.

The 29-year-old is in that position thanks to winning six of the season's first seven races but since then he has managed just one podium place.

Button was fifth at the Singapore Grand Prix yesterday having passed just one car - the Williams of Kazuki Nakajima - during the 61-lap race, which was won following a dominant drive by Lewis Hamilton.

But crucially Button stretched his lead to 15 points after finishing one place ahead of Barrichello and the Briton said: "It's like a victory to get these points - it was almost the perfect race for me."

Whitmarsh agreed and now expects Button to take the title.

The McLaren chief said: "It is not the most exciting way to win the championship but I think you have to score the points.

"Jenson is under a lot of pressure and when you have not won a world championship there is enormous pressure there, especially if it is your team-mate who is challenging you.

"I think he did a solid job here and though it is not mathematically done yet, it looks like he has got the championship, which is fantastic."

However, Whitmarsh did have a warning for Button as he can recall what happened to Lewis Hamilton in 2007 when the McLaren driver led by 17 points with two races to go, yet still missed out.

"I am sure Jenson will go away from this event feeling more relaxed but he will still have some tension," added Whitmarsh. "It's very easy to crash out at the next event with Rubens winning, which will be a 10point swing - and we've been there, the last two seasons have been like that for us. He has to stay calm."

Mathematically, only Sebastian Vettel can catch the Brawn GP pair but, 25 points behind with just 30 points remaining on offer, Vettel's chances look to have evaporated.

Brawn are also 42.5 points clear in the constructors' championship but their team boss refused to start any celebrations early.

A cautious Ross Brawn said: "I've been to many world titles where I have lost them at the last race. So, it is not done yet."

Brawn also insisted he would be doing Button no favours at the race in Suzuka despite the extent of the Briton's lead over his team-mate.

"This is as good as I've ever seen it in terms of two drivers trying to win the title," added Brawn. "And as for team orders, that just simply does not apply. I think the two drivers of the calibre we have got, you cannot separate one out unless it becomes mathematically impossible to win."

Fernando Alonso, who boosted Renault following a tough week amid the Crashgate scandal with third place, is tipped to be unveiled as a Ferrari driver next weekend.

The two-time world champion, who dedicated his podium place in Singapore to his banned former team boss Flavio Briatore, is expected to be named as Kimi Raikkonen's replacement with the Finn tipped for a return to McLaren as Hamilton's team-mate.

It is anticipated that BMW Sauber driver Robert Kubica will then fill the vacant seat at Renault left by Alonso.