Jacques Villeneuve has questioned Michael Schumacher's "motivation" ahead of the second season of the seven time world champion's comeback.
"I followed his return with attention and he is still fit and fast," said French Canadian Villeneuve, who beat Schumacher to the 1997 title after a close and controversial contest.
Last year he was smiling even after a bad result
But Villeneuve, who is approaching his 40th birthday, thinks the "expectations were too high" when the great German returned after three years of retirement.
"Everyone thought he was going to be a second faster than Nico Rosberg," he is quoted by L'Equipe in France.
"But when he was at Ferrari he was only a tenth in front of Rubens Barrichello. And over time, in people's minds, a tenth became a second.
"It took him (Schumacher) some time but he didn't do too badly. But what is his real motivation?" wondered Villeneuve.
"Last year he was smiling even after a bad result," he added.
Villeneuve admits his 2011 favourite is Fernando Alonso.
"He is a Spanish bull, nothing can stop him," he laughed. "He always gets the best out of each situation and has shown he can win with an average car and bring a team forward all by himself."
Villeneuve, meanwhile, is a critic of F1's newer generation of circuits.
"These modern circuits; you see nothing, the grandstands are too far from the track. There is no sense of speed, you don't appreciate the drivers' risks.
"Anyone playing a video game thinks he can do the same thing," he added.