Lewis Hamilton joked about needing a trip to the dentist after enduring a bumpy ride during practice ahead of this weekend's United States Grand Prix.
This race marks the 10th anniversary of Formula 1's first trip to the Circuit of the Americas in Austin, Texas. During that time it has come to be regarded as one of the best tracks on the schedule, but also one of the bumpiest.
Even though the teams have got much more of a handle on the porpoising problems that plagued them early in the season, it meant a less-than-comfortable ride for many on Friday. As was the case earlier this year, Mercedes were again one of the teams most affected by the bouncing.
After the session, Hamilton told reporters that even with the improvements made by the team, his W13 is still a lot less comfortable to drive than cars from previous years when things get a little bumpy. "I came here after Montreal and I drove last year’s car and it was so good," he said.
"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 biofuels.
"The car is so stiff now. Coming and driving the car, luckily I don't actually have many [dental] fillings because, if I did, they would have all come out this year, for sure. It's just so, so bumpy. I'm really praying for a non-bumpy car next year."

He will hope the porpoising will not affect him as much as it did earlier in the year. Such was the severity of the bouncing, especially at the Azerbaijan Grand Prix, the Brit was left with some severe back pain which, at one point, made him an injury doubt for the next race.
His team principal Toto Wolff has also shared his concern about the porpoising phenomenon. He went as far as to speculate that, if left unchecked, it might lead to some drivers suffering "brain damage" after prolonged exposure.
Despite the bouncing, Hamilton is quietly confident of a decent showing in Austin this weekend. "I kept the car in one piece today, which is good, and definitely felt improvements in the car," he added. "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."