Lewis Hamilton has blamed being down on power against Formula 1 rivals Red Bull-Honda and Ferrari for Mercedes failing to get on the Brazilian Grand Prix front row.
The world champion ended up third on the grid at Interlagos, just 0.191 seconds behind pole position man Max Verstappen, but says his fate was pretty much sealed by how much quicker his rivals are on the straight.
"We seemed quite competitive in P3 but then we seem to lose when we're going into qualifying, or they gain," he said.
"But nonetheless, I'm really happy that I was able to divide the Ferraris.
"It's always a tough challenge, but we've been down on power, I guess, compared to the others particularly.
"That's where we lose most of our time. But nonetheless I gave it absolutely everything I had."
Hamilton said that the time loss on the straights was "quite a chunk", with Mercedes having recently suggested that its engine does not perform as well at high altitude as some of its competitors.
But Hamilton felt he was able to get everything possible out of the car around the rest of the lap.
"I just kept chipping away at it," he said. "The last lap was actually as good as it could be for us, and the car felt pretty good.
"We were just lacking a bit of pace on the straights. But hopefully tomorrow that will be good in terms of [tyre] longevity."
Having sealed his sixth F1 title at Austin a fortnight ago, Hamilton has suggested he will use the remaining two grands prix to 'experiment' and start preparing for 2020.
But he suggested his approach to race day would be no different to usual.
"My approach has been pretty much the same way all year long," he said. "But maybe we can try and be a bit more aggressive tomorrow.
"I don't particularly see there is any reason to make any changes from where I am today. So I will continue like that."
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