Lewis Hamilton has said that he has "more work" to do in acclimating to his Mercedes car ahead of the final race of the season in Brazil.
The 28-year-old made the move from McLaren at the end of last season and is currently third in the drivers' championship.
"I did my best out there but I'm struggling," he told AutoSport after qualifying fifth at Interlagos. "There's not really much more I can say.
"When I was at McLaren, I knew the car. I was there for a long, long time and it suited me easier than the one I'm driving right now. I've just got to do some more work."
Sebastian Vettel claimed pole position for the Brazilian Grand Prix.
