Michael Schumacher has said he may still race for Ferrari in F1 again, either this year or next.
The seven-time world champion was forced to abandon plans to return at Valencia after experiencing neck pain following a test in an F2007
"Speculation in this business is pretty natural," said Schumacher. "Lots of people have their own opinions and thoughts but the fact of the matter is that 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.
"You can imagine that I obviously do feel kind of frustrated and quite sad because due to the circumstances I wasn't exactly expecting to be ready, but because of what happened I was obviously available to support the team and everybody.
"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."
Schumacher added that he believes Luca Badoer is the right man to step in and replace the injured Felipe Massa in the European GP.
"Luca is a very good friend," Schumacher added. "He has prepared himself quite strongly to be ready for all the years because this was his main job - to be ready in case something happened.
"So he is not somebody that has been sitting quietly around not doing anything. He has always been ready and naturally he has worked out very hard since Felipe's accident. We had said that I first need to confirm if I physically could do it and therefore it was always normal for him to keep himself on the fitness level he would need.