Lewis Hamilton believes that tyre management will be crucial during this weekend's German Grand Prix following high temperatures in Friday's practice sessions.
Temperatures peaked at 33c, with the track surface registering 58c during the second session.
The Brit ended the day on top of the leaderboard as he bids for his sixth win of the year.
"It was quite difficult to find the balance with the track being so hot and it is a tricky circuit to drive in general," he said.
"The car is a bit different now as everyone made some setup changes in a different direction to what we've had in the past, but it's still fun to drive. As the temperatures were so high, it was difficult for the tyres and we're going to need to manage that carefully when we get to the race."
Team-mate Nico Rosberg was just 0.024s behind in second place but admits it wasn't the easiest of days for 2014's dominant outfit.
"It was a difficult day for us, because we had to work on some of the new settings as the car was running without the FRIC [Front and Rear Interconnected Suspension] system," he said.
"But it worked out quite well even in difficult conditions. It was very hot outside and the soft tyres don't last that long here, so this will be tricky for the race."