Pirelli boss Paul Hembery believes Mercedes are still struggling with high tyre degradation levels, following Nico Rosberg's three-stop strategy at the 2013 F1 Canadian Grand Prix on Sunday.
Rosberg was the only one of the front runners who stopped three times in Montreal, after choosing not to switch to the medium compound following his first stint on the super softs.
Mercedes posted third and fifth place finishes on Sunday, with Lewis Hamilton taking his third podium of the season. But Hembery believes that a three-stop strategy showed Mercedes vulnerability with regard to tyres: “Mercedes still seem to be suffering from high levels of degradation,” he said.
“Nico Rosberg was the only driver in the top 10 having to use a three-stop strategy. While two stops was clearly the way to go.
“Paul Di Resta drove an excellent race to show what was possible with a one-stopper, completing 56 laps on his first set of medium tyres.”
The Pirelli chief also admitted it was a step into the unknown for the tyre supplier this weekend, as they faced contrasting conditions across the weekend: “The Canadian Grand Prix was a slight step into the unknown for everybody,” Hembery added.
“Canada is one of the most challenging circuits for the rear tyres due to high traction demands– particularly after it has rained previously in the weekend, because the moisture has the effect of washing away all the rubber that has been laid down before, which decreases grip levels further.
“Despite that, wear and degradation was under control for all the frontrunners and there was little of the graining that is a common feature of this race as well.”