Lewis Hamilton aired his frustration with his Mercedes after struggling during the first two practice sessions in Hungary, insisting the handling was "at its worst".
Seven-time world champion Hamilton finished FP2 in 16th place, with team-mate George Russell the slowest overall, and failed to record a time earlier in the day.
The timesheets had been disrupted somewhat, however, after some teams ran with one set of tyres in a bid to brace themselves for the altered qualifying format.
But Hamilton was in no mood for excuses and took aim at his sluggish machine before airing his hope that improvements would be made overnight.
"Wasn't feeling good at all," he said. "It was feeling like the car is at its worst today.
"We'll work on the setup tonight and hopefully tomorrow, usually last year it felt terrible at the beginning and then we turned it around with some setup changes.
"So, we'll work on that tonight and hopefully tomorrow we'll feel better."
Russell, meanwhile, struck a more optimistic tone and attributed Mercedes' sluggishness to the way they deployed their tyres.
"It didn't feel too bad in all honesty," he said. "It was obviously on very different programmes to everybody else.
"We only used one set of tyres throughout - it was a set of used tyres from FP1. The lap times don't really give a true representation and I am sure we will be better.
"We're just focused on trying to improve. We always know we tend to get better as the weekend progresses which is the right way round to be."