Mercedes driver Lewis Hamilton admitted he was feeling somewhat unsettled at the end of Friday practice in Austin, because of the bumpy nature of the track surface at the Circuit of the Americas.
Even so, Hamilton was third fastest in FP1 with team mate George Russell back in seventh place. The second practice was given over to a Pirelli tyre test meaning that the times and order were entirely unrepresentative.
"Luckily I don’t actually have many fillings because if I did they would have all come out this year for sure!" he said. "It’s just so, so bumpy. I’m really praying for a non-bumpy car next year.”
"[This year's] car is so stiff now," he explained to the media afterwards. “I came here after Montreal and I drove last year’s car and it was so good.
“I remember getting out and just beaming from ear to ear because it was so smooth and had good downforce, good power. This year obviously we lost a bit of power with the [introduction of] biofuels."
Even though he said the track's bumps had been "horrible" in the W13, he was otherwise feeling optimistic about how Mercedes could fare this weekend after introducing more upgrades to the car for the United States Grand Prix.
“I kept the car in one piece today, which is good, and definitely felt improvements in the car,” he reported. “Obviously [FP2] was a bit of a waste of a session in terms of performance, but FP1 was feeling quite good.
“Everything went to plan,” he insisted. “I’m hoping we make some changes tonight and we’ll find out tomorrow exactly where we stand, but it doesn’t feel like we’re too far away from everyone.”
Hamilton has just four races remaining in which to claim his first win of the year, and thereby extend an unbroken run of at least one victory per season that goes all the way back to his debut in the 2007 Australian Grand Prix.
“I’m super-grateful to everyone back to the factory for working so hard and bringing us an upgrade this weekend," he said.
“It’s been a tough year for everyone at the factory," he continued. "For them to continuously be pushing and keeping their heads down and really putting out these new pieces, I’m super-grateful.”
Russell was also feeling upbeat about how the day had gone and optimistic about what they could achieve on Saturday and Sunday.
“I’d like to think that we’ll be ahead of the midfield cars this weekend but I’ve learnt in this sport to take nothing for granted," he acknowledged.
“I think we’ll be okay,” he added. “We should hopefully be in Q3 and fighting for those top six positions.
"We’re going to work as hard as we can overnight, try and make sure we’ve got a fast car. Pole is always a stretch for us but the race is on Sunday so I think we’ve got half a chance.”
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