Toro Rosso Formula 1 driver Daniil Kvyat has described his penalty for colliding with Sergio Perez on the final lap of the United States Grand Prix as "stupid" and "unacceptable".
Kvyat lunged down the inside of Perez at the Turn 15 right-hander, slamming into the left front-wing endplate of the Racing Point with his right front tyre and forcing Perez off.
Perez rejoined and stayed side-by-side with Kvyat despite the contact, but the Russian completed the move around the outside of the following corner to secure 10th on the road - only to be assessed a five-second penalty after the race that dropped him to 12th.
When made aware of the penalty post-race, Toro Rosso driver Kvyat told Ziggo Sport: "That's bullshit. That's unbelievable. I don't know, I have no words. It's so stupid.
"I just went around the inside and he closed the door, it's normal. And then we touched and I overtook him around the outside.
"It [the decision] is unacceptable."
It is the second time in two races Kvyat has disagreed with a post-race penalty decision that cost him a points finish, after he was penalised for colliding with Nico Hulkenberg on the final lap of last weekend's Mexican GP.
Discussing Kvyat's move at Austin, Perez reckoned the Toro Rosso driver did not slow down as much for yellow flags waved at Turn 12 for Kevin Magnussen's stricken Haas, and was therefore in range to launch his attack.
"I think at the end Kvyat just overdid it too much, under the yellow flag he didn't lift, he attacked me straight away after the yellow flag and then into [Turn] 15 he just crashed into me," said Perez.
The penalty decision puts Perez's Racing Point team one point clear of Toro Rosso in the fight for sixth in the constructors' championship.
Toro Rosso's other driver Gasly clashed with Perez three laps prior to his team-mate Kvyat, as he tried to fend off the Mexican for ninth place, but sustained damage and was ultimately forced into retirement.
"Three laps toward the end we started to fight with Sergio, and we came together in Turn 13," Gasly explained.
"Turn 12 [we were] already crossing and battling. He went down the inside in Turn 13, and then we just touched with my front right tyre, and just bent the front right suspension."
Asked whether either driver was at fault for the incident, Gasly said: "Honestly, whatever it is, it's not going to give me back the points that were on the table.
"I don't know. I will have a look at the video, see what's happened.
"I don't think there was anything big, but unfortunately it was just enough to bend the suspension and to end our race."
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