Button may not have his way in Monaco

(GETTY IMAGES)

Sunday's showcase Monaco Grand Prix could be the most open in years, even if Formula One championship leader Jenson Button will still be very much the man to beat.

The Briton, a Monaco resident, has won four of the season's five races and will feel completely at home on the Mediterranean principality's tight and twisting streets.

However the harbourside circuit with its unforgiving barriers and blind corners has made a mockery of predictions in the past, particularly if it rains.

With overtaking next to impossible, qualifying will be crucial.

Button's Brawn GP team mate Rubens Barrichello, who celebrates his 37th birthday on Saturday before his 17th appearance in the glamour showcase of the season, is hungry for his first win since 2004.

In the slowest race on the calendar, McLaren's world champion Lewis Hamilton and the Ferrari pairing of Felipe Massa and Kimi Raikkonen could also be dangerous while Renault's Fernando Alonso and Toyota's Jarno Trulli are past Monaco winners.

Red Bull's Australian Mark Webber has always stood out while German team mate Sebastian Vettel can add to the growing comparisons with retired compatriot Michael Schumacher.

"It is very different and it is 'chuck all the downforce on' and don't worry about the drag and see what happens," said Button of the challenge ahead at a circuit where he crashed heavily in practice in 2003 and had to miss the race.

"Monaco is a circuit where I need to get the best out of the car and maybe change my style a bit from the first four races.

"When Red Bull have a clear shot at it and they do everything right, they are going to be competitive and we can't forget that ... they are going to be on us in Monaco for sure."

Hamilton, winner last year and second in his astonishing rookie season, has been in love with Monaco since the days when Brazilian Ayrton Senna dominated with Lotus and McLaren.

"It's always a shock to my system when you get on that track and realise the speed you are doing with all these barriers around you," the 24-year-old Briton told Reuters.

"It's very, very special to drive that circuit and I really hope that the car works better there, especially with the slower speed corners.

"We'll be able to be a little closer," added the champion, whose title defence could be over by the summer break after he scored just nine points in the first five races compared to Button's 41.

While 2007 champion Raikkonen won for McLaren in 2005, Brazilian Massa has been on the podium on his last two visits there and desperately needs a third to fire up Ferrari's worst ever start to a season.

"It would be great to go for a hat-trick this time," he said on the Ferrari website (http://www.ferrariworld.com)

"It will be very tough, but we'll give it our best shot. Thanks to the aerodynamic updates we introduced in Spain, the F60 is much improved," added the Brazilian who scored his first points of the year at the last race in Barcelona.

"In terms of performance, we have made significant steps forward, while there is still much to do on the reliability front."