Nico Rosberg says he is confident Mercedes can get on top of the testing conditions for the Belgian Grand Prix as Spa-Francorchamps bakes in higher-than-expected temperatures.

With air temperatures alone surpassing 35 degrees in the afternoon, tougher than expected track conditions have been wreaking havoc on the rear tyres, particularly using the supersoft rubber.

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Significantly, Mercedes was the only team to use the supersoft rubber in the morning, with Rosberg going seven tenths quicker than team-mate Lewis Hamilton, but chose to avoid it in the afternoon as the German turned in the sixth best time.

Though Rosberg admits the conditions are keeping Mercedes on its toes, he is confident it can overcome the challenges.

"It's just really, really hot. It feels like I'm back in Ibiza, just unbelievable. That just makes it very, very difficult for the rear tyres."

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"It's an added challenge. It really is tough out there to manage that, so we're working on it and we need to do a better job than everyone else."

Meanwhile, Rosberg set his pace setting FP1 time with the Halo attached, the German using the cockpit protection prototype for the first time.

"No problem at all [through Eau Rouge], you don't even notice the top part. I think they can even come down with that because LMP1 is lower anyways. So for sure they could go lower."

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