Mark Webber suspects Michael Schumacher's headline time at the Jerez test last Friday was little more than a publicity stunt.

One day after Nico Rosberg had expressed concerns about the new Mercedes, team-mate Schumacher recorded the fastest time of the week using the super-soft Pirelli tyres. Webber, who drives for the reigning champion Red Bull team, noted that after Schumacher's chart-topping lap, "he was immediately two seconds off the pace once again".

"It was probably just a little show for Germany," he added. "The super-soft tyre is much faster but they only last for one lap."

Schumacher denied his lap time was a ploy to ease the pressure building up on Mercedes, pointing out that it was set with a reasonable amount of fuel on board.

"I was on a ten-lap run, so I don't know if you can call that very short," he said. "It is also true that we are not the only team to have tried these tyres."

It has also been suggested that Nick Heidfeld's quick time at Jerez on Saturday was to appease Renault's sponsors in the wake of Robert Kubica's crash, while Rubens Barrichello topped the timesheets just two weeks before Williams floats on the stock market. McLaren's Jenson Button explained that the new super-soft tyres have made lap times even more difficult to read

"There are big differences between the different types of tyres," he said. And Bruno Senna added: "The difference between the hard and the super-soft, I would say is 1.5 to 1.7 seconds."

But Felipe Massa said it was no surprise to see Schumacher quickest on Friday.

"Schumi in front? This is not news, he's won more than any of us."