Michael Schumacher today would not rule out another attempt at resurrecting his Formula One career with Ferrari.

Speculation that the seven-time world champion might compete in another full season was fuelled by news that Ferrari president Luca di Montezemolo is pushing for the top teams to be allowed to run three cars in 2010.

Were that to happen, di Montezemolo told the Italian newspaper La Stampa that Ferrari's third car could be offered to Schumacher. "Michael is 40 but he is from another planet," he said.

Yesterday the German admitted defeat, on fitness grounds, in his attempt to make a comeback as a replacement for the injured Felipe Massa at next week's European Grand Prix in Valencia.

Twenty fours hour later, though, he was intriguingly vague when asked about his future.

Schumacher, who retired at the end of the 2006 season, said: "Lots of people have their own opinions and thoughts, but the fact of the matter is I'm very disappointed not to do what I was looking to do. That's all that I'm really thinking about and have to digest somehow."

Having tested a two-year-old Ferrari at the Mugello circuit in Italy on Monday, Schumacher was ruled out of an immediate return to Formula One because of the lingering effects of a neck injury he sustained in a motorcycle accident in February.

The damage suffered meant he would not be able to cope with the high G-forces generated during a full Grand Prix lasting more than 90 minutes.

He said: "You can imagine that I feel frustrated and quite sad, because due to the circumstances [of Massa's accident] I wasn't exactly expecting to be ready.

"We have prepared ourselves very seriously, we have done as much as we could do from our side.

"But right from the beginning, Ferrari and ourselves always mentioned that I would do the job under the condition of being ready for it. It's sad that in the end I couldn't fulfil this target."

Massa's place alongside Kimi Raikkonen will now be taken by Ferrari test driver Luca Badoer. Even though the veteran Italian has never scored a point, nor raced since 1999, his call-up won Schumacher's support.

He said: "Luca has prepared himself quite strongly because this was his main job, to be ready in case something happened.

"Yes, he hasn't raced for a long time, but a racer doesn't lose the racing spirit and I wish him well."

Massa is expected to be out for the season after fracturing his skull in a freak accident during practice for the Hungarian Grand Prix last month.

Schumacher added: "We spoke yesterday and he is good and motivated to get back as soon as possible."