Singapore was a “one-off” stint at the wheel of team regular Sakon Yamamoto’s car, HRT reserve driver Christian Klien said after Sunday’s night race.

Despite the struggling Spanish team saying Yamamoto was sidelined due to food poisoning, Klien’s graduation to the race seat coincided with the arrival of the logo of a new Austrian sponsor on the Cosworth-powered car.

Paddock sources also said one of Yamamoto’s personal sponsors was removed from the car in Singapore.

So just as Karun Chandhok and Bruno Senna have also been sidelined by HRT earlier in 2010, paddock cynics now expect the Japanese to have to make way for the better-funded Klien.

The 27-year-old former Jaguar and Red Bull driver also performed well in Singapore, considerably outqualifying teammate Senna before retiring from the race with an hydraulic problem whilst running 18th.

When asked about the future, Klien answered: “Singapore was a one-off to replace Sakon Yamamoto.  Anything else is not in my hands.

“It was really great to be feeling like a proper racing driver again and I do hope I could make my mark this weekend.”

He was less flattering about the Dallara-designed F110 car.

“It behaves just like a rally car,” he told Finnish newspaper Turun Sanomat, before joking: “I should probably ask Kimi Raikkonen for advice.”