'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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Phillip van Osten

Motor racing was a backdrop from the outset in Phillip van Osten's life. Born in Southern California, Phillip grew up with the sights and sounds of fast cars thanks to his father, Dick van Osten, an editor and writer for Auto Speed and Sport and Motor Trend. Phillip's passion for racing grew even more when his family moved to Europe and he became acquainted with the extraordinary world of Grand Prix racing. He was an early contributor to the monthly French F1i Magazine, often providing a historic or business perspective on Formula 1's affairs. In 2012, he co-authored along with fellow journalist Pierre Van Vliet the English-language adaptation of a limited edition book devoted to the great Belgian driver Jacky Ickx. He also authored "The American Legacy in Formula 1", a book which recounts the trials and tribulations of American drivers in Grand Prix racing. Phillip is also a commentator for Belgian broadcaster Be.TV for the US Indycar series.