'Impossible to be more proud of my son,' says Hartley's dad

Brendon Hartley is elated with his opportunity to race in Formula 1, but there's one man who is perhaps even more euphoric: his father, Bryan Hartley.

The Kiwi will race in next Sunday's US Grand Prix in Austin, replacing Pierre Gasly at Toro Rosso as the Frenchman's heads to Japan to try and win the Super Formula title in the series' ultimate round.

The 27-year-old's big F1 break comes late in his already rich career but the tardy debut takes nothing away from the excitement felt in the Hartley family.

"It would be impossible to be more proud than this," Bryan Hartley told New Zealand's RadioLIVE.

• Brendon Hartley ready for 'dream' F1 début

"This is truly, absolutely amazing, and every person involved in motorsport would love to be in my position right now.

"It all happened very quickly. It all happened behind the scenes and nobody knew what was going on, and it all just happened in the last couple of days."

Hartley's prospects beyond Austin are difficult to predict but the Toro Rosso's driver's father is sure his son will make the most of the unexpected opportunity.

"Hopefully in five years he will be in Formula One, but unfortunately it is hard to predict.

"What he has to do next weekend is finish. Anything than last in qualifying is a bonus for him, considering he hasn't done any mileage or simulation testing.

"I know from my own experience when you put the helmet on and when the green flag goes down, you forget about the world around you and you get on with the job at hand, getting to the chequered flag, and he is good at that."

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