Heidfeld says he has done enough to be in Formula 1 next year

The German driver, who was without a racing seat prior to the start of the season, was drafted in to replace Robert Kubica at Renault following the Pole's accident during a rally in February.

Heidfeld scored a podium for Renault in the second race of the year, but has been unable to emulate that sort of performance since then.

Heidfeld will be replaced by Bruno Senna in tomorrow's first practice for the Hungarian GP, while Romain Grosjean's praise by team boss Eric Boullier has triggered speculation that the Frenchman could take Heidfeld's seat this year.

Heidfeld says, however, that while his season has not been perfect, he is calm about his future.

"I'm happy with where I am with the team. I think we all get on well," said Heidfeld on Thursday. "Bruno gets the chance to drive here, and I think Eric said Grosjean is doing a good job in GP2, but that doesn't mean that he's going to take my seat."

He added: "I don't think it has been a perfect season so far, but I think it's been good and certainly good enough to fight for a seat next year. I will obviously keep on pushing and try to do my best and then we'll see what happens."

The German admits his qualifying performance has not been great this season, but says he has learned a lot and is making progress all the time.

"I think there's been some very good performances. Obviously there were some races where I had some problems like in Barcelona where the car was on fire in qualifying, but still finished eighth.

"Overall I think I did well. I think in qualifying I did not always maximised the potential, but I learned a lot about it and I think it has been better. It's just small things but it explains why I struggle a bit."