Pecking order unclear as more rain falls at Spa
After a mostly wet day of running, even though the Belgian track was drying in the afternoon session, Mercedes' Norbert Haug was asked who he thought was looking quickest so far.
"Nobody knows exactly," he told German Sky television.
He said the timesheets threw up a few clues, with Red Bull "stronger than they seem" and also Force India's Adrian Sutil apparently in the running.
"Ferrari and McLaren will be good," added Haug, confirming that Mercedes is running a modified F-duct system this weekend.
"I don't think the pecking order has really changed. I also don't think we are making a great leap forward.
"We think the floor is working a little better, but we'll learn more about that on Saturday," added Mercedes' competition boss.
Haug gave a clearer prediction about the weekend weather forecast.
"I suspect Saturday will be wet as well," said the German, just as the GP2 race on Friday afternoon was stopped due to heavy rain.
Added Renault's chief engineer Alan Permane: "It's the same (forecast) for Sunday."