Brendon Hartley is the most likely candidate to step in for Toro Rosso at the United States Grand Prix, with the possibility of also receiving a full time drive next year.
A vacant seat in the Italian team needs to be occupied alongside Daniil Kvyat, after it was reported Pierre Gasly would return to Super Formula and compete in the title deciding round on the same weekend as the US GP.
It is believed Toro Rosso team principal Franz Tost wants to utilise the US GP weekend as a trial for the New Zealand driver, to ultimately assist in making the decision for next year, with Sebastien Buemi the back-up option.
Gasly is a clear favourite for one of the two seats available within the team for 2018, impressing in his appearances for the squad at the Malaysian and Japanese Grand Prix.
However, Tost and Red Bull are uncertain about the second seat.
27-year old Hartley has previously worked with Red Bull as their official test driver in 2009 and 2010, completing one test for Red Bull in 2008 and two for Toro Rosso in the following year.
He then went on to work with Mercedes in 2012 after being dropped from the Red Bull junior program, performing a young driver test at Magny-Cours for the former mentioned team.
Hartley currently obtains enough super-licence points to race in Formula One, but is still under contract with Porsche in the FIA World Endurance Championship, where he could win the title this weekend at Fuji.
On top of that, talks are also underway for Hartley to race for Chip Ganassi Racing next year in IndyCar, adding more contractual hurdles that need to be ironed out before his outing in Austin.
In updated information, Porsche have announced they will not stand in the way of Hartley’s potential F1 debut.
“At the moment, the story is just speculation, but from Porsche’s point of view, any request to do this would be no problem,” a Porsche spokesperson told Dailysportscar.
“The only restriction on any of our drivers after Le Mans is that they must not be in a situation where they are competing with Porsche or any other VAG brand. The same was the case when Brendon was racing and ultimately winning at Petit Le Mans last weekend.”
The United States Grand Prix takes place on October 20-22.