Title rivals Lewis Hamilton and Max Verstappen clashed in the second practice at the US Grand Prix, as Red Bull’s Sergio Perez emerged with the fastest time.
Unusually for a non-competitive Friday, there was a brief flashpoint between the title rivals, separated by just six points in the standings, during the opening day's running.
After Hamilton overtook Verstappen going into the final corner, following an incident in which the two raced side by side down the pit straight, Verstappen called Hamilton a "stupid idiot" over the radio.
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Verstappen then stuck his middle-finger up at Hamilton as they accelerated out of the corner.
Verstappen, who later aborted his qualifying simulations after being frustrated by traffic, said of the incident with Hamilton: "We were all lining up to go for our lap so I don't really understand what happened there."

Max Verstappen e Lewis Hamilton sono pronti ad incendiare la contesa nelle ultime 6 gare della stagione

Image credit: Getty Images

Hamilton set the fastest time of the session but it was ruled out for marginally exceeding track limits at Turn 19. The time he set was 0.1secs faster than Perez's quickest.
Verstappen, who leads Hamilton by six points in the title race with six races to go, did not set a representative time and ended up eighth in the session.
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