London, Feb. 2 (ANI): After his impressive test drive on Monday, Michael Schumacher underwent secret tests on his neck, fuelling fears that it could affect his F1 comeback.
The seven-time champ returned to the cockpit on Monday for the first time in three years, setting the third-fastest time for Mercedes in Valencia, The Sun reports.
Schumacher covered 40 laps after taking over from team-mate Nico Rosberg.
Ferrari miracle man Felipe Massa set the fastest time on his return following his 180mph shunt in Hungary last July. He needed life-saving brain surgery after a spring flew into his helmet and fractured his skull.
But the 41-year-old German deriver took the unusual step of having his personal doctor Johannes Peil at the track and underwent an exam on his neck at his motor-home after testing.
When asked if Schumacher's neck was fully healed, Dr Peil said: "We wait and see!"
Last year, Schumacher scrapped a temporary comeback with Ferrari after suffering the injury in a motorbike accident almost 12 months ago. (ANI)