Martin Brundle has described Red Bull’s lack of pace as the biggest surprise of the 2012 season so far.

After consecutive world championships with Sebastian Vettel, the energy drink-owned team was universally tipped as the pre-season favourite for yet another F1 title.

But McLaren dominated in Australia before Ferrari and Sauber surprisingly set the pace recently in Malaysia.

Former F1 driver Brundle admitted the struggling RB8 was the surprise of the opening salvo in 2012, but he also acknowledged that the turnaround might have been predicted.

“When you look at how the regulations have changed, it’s almost like they were designed to slow the Red Bulls down,” the Sky television commentator told the website of the BBC programme Top Gear.

“Doubling the torsional stiffness of the front wings, the way Red Bull were ‘flying’ their car down the track with lots of rake, nose close to the ground, exhausts helping to sort the high rear ride height out, it’s all been taken away from them,” added Brundle.

An unnamed engineer at Red Bull has admitted the team was caught on the hop in the winter pre-season, when it became clear McLaren was better prepared for the new rules.

“McLaren came with a (exhaust) system on the edge of legality,” the engineer told Germany’s Auto Bild, “and it was declared legal by the FIA.

“So (Adrian) Newey had to adapt,” he added, referring to Red Bull’s last-minute decision to change tack at the very end of the pre-season test period.

The message coming from the Milton Keynes based team, therefore, is that Red Bull is playing catch-up.

“We need to understand the car better,” admits team advisor Dr Helmut Marko, “which is why for the next race (in China) we will have hardly any new parts.”

So until he’s back at the front, F1′s formerly-dominant Vettel – who lashed out at backmarker Narain Karthikeyan recently in Malaysia – needs to adapt.

Asked if the German was justified in calling his Indian rival an “idiot”, Brundle insisted: “No.

“That’s just an angry man who hasn’t got a front-running car at the moment. He’s just frustrated.”

Bosses of the McLaren and Mercedes teams on Saturday signalled the end of F1′s latest flexible bodywork saga.

New FIA tests to ensure the rules compliance of the front wings and floors are taking effect this weekend and at Monza in two weeks, after Red Bull and Ferrari’s cars came under the spotlight.

McLaren team boss Martin Whitmarsh told reporters at Spa-Francorchamps that the offending wings are not flexing as much in Belgium.

“I wasn’t that confident that it (the problem) would be nailed but I have to say … the wings were of a different stiffness and positional domain than they had been in previous races,” he is quoted by Reuters.

Mercedes’ Ross Brawn added: “I think all of us can see that what was visible in the last couple of races doesn’t seem to be the case here.

“I don’t know what has happened but it looks visually to me to be different,” said the Briton.

Red Bull’s Mark Webber on Saturday secured pole for the Belgian grand prix, less than one tenth ahead of McLaren’s Lewis Hamilton.

Both Red Bull and Ferrari have said they are using identical wing designs this weekend to the ones raced in Hungary before the summer break.