Mercedes may have struggled to live with the pace of Ferrari and Red Bull during practice on Friday but Toto Wolff is not concerned about their Hungarian Grand Prix chances.

Lewis Hamilton and Valtteri Bottas finished fifth and sixth in both sessions at the Hungaroring, the latter more than a second slower than Sebastian Vettel in FP2.

Championship leader Hamilton struggled for momentum in the day's first outing, twice running wide as he tried to get to grips with the 4.381-kilometre circuit.

The same could not be said for title rival Vettel as he impressed on long runs, the German setting the fastest time of the day in FP2 as he clocked a 1:16.834.

That was nearly a second faster than Daniel Ricciardo's best of 1:17.613 earlier in the day as the Red Bulls showed good pace, sending an ominous sign to Mercedes for Sunday.

Silver Arrows boss Wolff was not fazed, though, and he is confident once tweaks are made to help their cars improve they will be competing for pole position in qualifying.

"It is very early days," he told a media conference. "Hungary is always very different to all the other tracks.

"The heat is just kicking in and through the sessions now we need to learn how to set the car up, and understand how the tyres perform and then eventually, hopefully, be ready [Saturday] afternoon."