Mercedes-Benz motorsport boss Norbert Haug believes that Red Bull's strong times at the start of the final preseason test at Barcelona will be comfortably eclipsed over the next few days.
Mark Webber ended the first morning more than one second clear of his nearest rivals after a series of short runs, but Haug was not alarmed by the pace of the RB6.
"If they did that time with 150 kilos [of fuel] then they were quick," he said. "But this time is not the benchmark. It's early days, and I would not say that any team has made any serious qualifying efforts so far. Later in the test I would think we will see it – if the weather stays dry, then I think we can have a feeling of what's going on."
Haug added that the increased size of the fuel tanks for this year due to the refueling ban has made testing times incredibly difficult to work out, but he feels that it will add a fascinating aspect to the racing this year.
"It's just impossible to judge – it's guesswork," he said. "If you have a 37-lap run for example, then you have a minimum fuel load – maybe 74 kilos. But that doesn't tell you the whole story because one guy could do the same run with 160. A difference of around 80 kilos could mean about three seconds per lap, but that's assuming the heavier guy can make the car work when they take the fuel out.
"With one setup you have to deliver a low-fuel run and an absolutely maximum fuel run. That's a wide range, and it's very different from anything we've ever had in Formula 1. So, you will probably find a car that is at the top of the times on low fuel, but is not so quick in race trim. That will make things pretty exciting."