Button: Red Bull has wasted chances
Red Bull have squandered chances to make the most of their speed advantage and rivals are now closing in, according to Formula One world champion Jenson Button.
"They haven't got it together as often as I had thought they would," the McLaren driver told Reuters ahead of Sunday's European Grand Prix, ninth of 19 races.
"Last race (in Canada) they were quite quick considering the type of circuit but again they finished fourth and fifth and it seems one of the cars always has an issue in the race and they need to back off," added the Briton.
"I don't know if it's because they always push the car to the limit which makes them very quick in qualifying but in the race they struggle."
Button, second in the overall standings and three points behind team mate Lewis Hamilton after two successive McLaren one-two finishes, said Red Bull were blindingly quick when everything worked out.
Australian Mark Webber showed that with back to back wins in Spain and Monaco while Germany's Sebastian Vettel led a one-two in Malaysia. However the two Red Bulls also lost a one-two in Turkey when they collided.
"When they get it together they are awesomely quick," said Button, winner of two races this year.
"But more often than not they seem to have got it wrong somehow, be it reliability or strategy mistakes or crashing into each other."
Red Bull have made the most of a 'blown diffuser' which increases downforce by channelling exhaust gases in an aerodynamically efficient manner through the rear of the car.
Ferrari have introduced the same system to their car this weekend however.
"We brought a lot of improvements here, more for Silverstone, more in Germany, so we are pushing very, very hard," Ferrari technical director Aldo Costa told reporters.
"We have got a new radiator system in terms of the shape and concept so there's new bodywork. And the exhaust layout is completely different and the back of the car, floor, suspension. There are improvements as well in the middle part of the car."
Button warned Renault and Mercedes also looked quick.
Webber and Vettel have meanwhile been experimenting with an 'F-duct' similar to that pioneered by McLaren to increase straight line speed.
"We need to look at it more," Webber said after setting the third fastest time in Friday practice.
"It is not without its challenges so I'm not sure if we will race it yet. It's better but whether it's good enough we will see." YahooXtra Sports