Apr.18 (GMM) Rising Red Bull-backed youngster Brendon Hartley is not yet knocking on the door of a formula one race seat, his manager insists.

After giving Toro Rosso's 2008 car its debut shakedown recently, and conducting a Red Bull demonstration in Saudi Arabia in March, some reports suggested that the 18-year-old from New Zealand might be high on the list to replace Red Bull Racing-bound Sebastian Vettel at the Italian team next year.

But although admitting that Hartley is heading in the right direction, his manager, mentor and countryman Peter Johnston insists that the first step is to secure the British F3 title.

"In the near future, a F1 drive is not possible," he told the news agency NZPA.

"He has to do very well this year and then move on to GP2. He is doing some component testing for Toro Rosso but that is all it is.

"If he does good this year, he could become a full time test driver with Toro Rosso next year," Johnston added.