Michael Schumacher's return to Formula One could be in jeopardy due to a neck injury the seven-time World Champion sustained while testing a motorcycle in Spain earlier this year.

According to a (awkwardly translated) release from Schumacher's spokeswoman, Sabine Kehm, "It is not sure yet the neck will hold and the comeback can be started."

Schumi's physical fitness has been tested over the past week as the 40-year-old racer prepares to replace Felipe Massa for the duration of the 2009 F1 season, beginning with the European Grand Prix in Valencia on August 23.

"I'm currently in the midst of my preparations for the upcoming race. I already lost three kilograms even if it is also important to me to build up muscles." Schumacher said on his official site yesterday, "So all in all, the practice works pretty well. I only have to admit that my neck pinches a bit."

It's unclear if and/or when the FIA will sign-off on Schumacher's physical fitness, although we'd expect an announcement sometime late next week.

[Source: BBC]