'Stupid idiot': Verstappen-Hamilton feud erupts in ugly practice spat

Max Verstappen has labelled Lewis Hamilton a "stupid idiot" as the F1 rivals' nasty feud continued on the opening day of practice for the United States Grand Prix.

Hamilton, who is six points behind Verstappen in the championship, overtook the Red Bull driver at the concluding left-hander in Friday's second session in Austin.

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Verstappen was temporarily forced off the track before racing wheel-to-wheel with Hamilton on the start-finish straight at 290km/h.

Hamilton held the inside line heading into the opening bend, with Verstappen eventually conceding the position.

Hamilton raced off into the distance as Verstappen could be heard labelling his rival a "stupid idiot" over team radio before flipping him the middle finger.

"Ignore it, don't worry about it," Verstappen's race engineer Gianpiero Lambiase responded.

Verstappen was forced to abandon a further two laps due to traffic, sparking another angry outburst from inside the Dutchman's helmet.

"I'm boxing - f*** this," he yelled, returning to the pits in disgust.

Without posting a representative qualifying time, Verstappen finished back in eighth, 0.878 seconds behind Sergio Perez who set the pace in the other Red Bull.

McLaren's Lando Norris took second, with Hamilton third and three 10ths adrift of Perez.

Verstappen is chasing his first championship in Formula One, while Hamilton has seven.

An eighth would push Hamilton ahead of Michael Schumacher for the most in F1 history.

Concerns for Mercedes over engine problems

Valtteri Bottas, who finished fastest in the opening one-hour running at a sizzling Circuit of the Americas, ended the final action of the day in fourth.

The Finnish driver will serve a five-place grid penalty for Sunday's race after taking on his sixth Internal Combustion Engine of the campaign.

There will be cause for concern at Mercedes with Williams' George Russell and Aston Martin driver Sebastian Vettel also due to serve engine penalties here for change of parts.

Both drivers are powered by Mercedes.

Fernando Alonso, who broke down in the opening minutes of the morning action, then suffered a big spin off at the penultimate corner later in the day, exiting backwards into the gravel before limping back to the pits.

F1 is back in America for the first time in two years and the grandstands were packed for Friday's action, with more than 140,000 fans - the greatest attendance figures of the season so far - expected for Sunday's race.

Earlier, Sergio Perez and Mick Schumacher collided in the closing moments of the first session.

Both drivers emerged from the coming together at Turn 12 without damage, but Perez took aim at the German rookie.

"What an idiot," said the Mexican. "He isn't looking in his mirrors."

with AAP

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