Mark Webber won from pole in Barcelona on Sunday with only brake problems for team-mate Sebastian Vettel preventing a second Red Bull one-two in three races.

“I think the Monaco result is extremely tough to call,” said Button.

“There are a lot of very competitive drivers so there is a good chance of a slightly unpredictable race.”

Red Bull’s speed this season has meant that they have taken pole for all five of this year’s races, and only twice has any other team intruded on the front row in qualifying.

As a team, we’re really excited about Monaco

Jenson Button
Their advantage over the rest of the field appeared to have widened still further with the installation of a comprehensive upgrade package at the Circuit de Catalunya.

Webber’s was 0.834 seconds faster than third-placed Lewis Hamilton in qualifying, with only Vettel able to get close to his team-mate.

Button himself had described the Red Bulls as “untouchable” in Spain but is confident Monaco’s tight street circuit will help level the playing field.

“To get the best out of the weekend, you’ve really got to build your speed up gradually,” he said.

“There are no benefits from attacking from lap one and risking a mistake.

MARTIN BRUNDLE’S COLUMN
Jenson Button had a bad day at the office in Spain, although he described it more colourfully to me at breakfast in Monaco on Monday

“The track rubbers in incredibly quickly over the weekend, and it’s all about letting the car naturally find more speed through the corners as the conditions improve and your confidence increases.

“Hopefully we won’t have the same gap to the Red Bulls that we had in Spain and I don’t think we will. As a team we’re really excited about that race.”

Button’s team-mate Lewis Hamilton, who was running second to Webber when a tyre deflation caused him to crash on the penultimate lap in Spain, is also hopeful of a good weekend in Monaco.

“Qualifying will be more important than ever,” Hamilton said. “While we’re still working hard to improve our qualifying pace, Monaco is a place where the input of the driver is more important than at any other track, so I’m pretty confident that we’ll be able to do a good job.”

Some reliability problems, particular affecting Vettel, have contributed to the Red Bull duo failing to convert their pace into points.

Vettel is 10 points behind Button with Webber a further seven adrift.

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Button frustrated by mechanical problems
But Webber is confident that his team can claim another win at Monaco if they stay ahead of their rivals in qualifying.

“The whole atmosphere is good and it is a special grand prix. We all know that front row will be king there as well,” he said.

“It is a one-off on the calendar. It is a sensational challenge for the drivers, we all like going there. You certainly couldn’t have a track like it now if you wanted to design and build one.”

From BBC Formula Sport