Sep.21 (GMM) Kimi Raikkonen almost sat out the Singapore Grand Prix weekend with a back injury, it emerged on Saturday.

So serious was the problem that Lotus briefed reserve driver Davide Valsecchi to prepare to step into the Finn's car.

But Raikkonen did manage to practice and qualify on Saturday, although he admitted that before arriving at the street circuit for the day's action, he doubted he would be able to.

"This morning it was very difficult," he is quoted by the German broadcaster Sky, amid a fraught and tense weekend after he revealed he decided to leave Lotus for Ferrari in 2014 because he hasn't been paid.

Sky said Raikkonen is suffering from a pinched nerve; an injury he has had before.

Kimi Raikkonen, Lotus F1 Team with the media
Kimi Raikkonen, Lotus F1 Team with the media

Photo by: XPB Images

"At breakfast I thought I wouldn't be able to drive," he admitted.

Raikkonen was given pain killers and underwent treatment by doctors and a physio, and the 2007 world champion said "it worked".

But he wasn't at 100 per cent, particularly in morning practice where he therefore struggled find a good setup for qualifying.

He qualified just 13th, while in the sister car Romain Grosjean was third.

"In the afternoon it was not really ideal, but at least the car is on the grid. For tomorrow we will see," added Raikkonen.

Because Raikkonen qualified the car, Valsecchi or another reserve is no longer allowed to step in to substitute.