Former F1 driver 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 team was universally tipped as the pre-season favourite for yet another F1 title. Then, at the start of the season, McLaren dominated in Australia before Ferrari and Sauber surprisingly set the pace recently in Malaysia.PLAYING CATCH-UPFormer F1 driver Brundle agreed the struggling RB8 was the surprise of the opening salvo in 2012 but 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," he said. "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."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. He told Germany's Auto Bild: "McLaren came with a (exhaust) system on the edge of legality and it was declared legal by the FIA. So (Adrian) Newey had to adapt (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 UK-based team, therefore, is that Red Bull is playing catch-up.Team adviser Helmut Marko said: "We need to understand the car better, 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."