Niki Lauda, who knows what it is takes to fight back from life-threatening injuries, says he was shocked to hear of Michael Schumacher's injuries.
The seven-time World Champion suffers severe head injuries in a skiing accident on Sunday and remains in a critical condition in a French hospital.
Schumacher's injuries have stunned the motor racing world especially as they came in his retirement after 19 relatively safe years in Formula Onen.
"I find it completely shocking and unexplainable why this great driver, who won seven Championships in over 300 races and stayed alive, could have something like this happen to him. It's tragic," Lauda told The Guardian.
"He was the greatest driver of them all, with seven titles. Only the great Juan Manuel Fangio comes close to him, with five. He was the perfect racer, with speed, instinct and a great technical understanding."
He added: "Michael is a very good skier and what happened to him could have happened to anyone. He's a perfect man, a solid man, an outstanding guy.
"He would not take unnecessary risks. He's not stupid. I certainly would not expect him to do something crazy in front of his own son."