2019 is "make or break" for Sebastian Vettel.
"It's make or break for Sebastian Vettel this season," the outspoken Canadian told Le Journal de Montreal.
"He has made mistakes in recent years that have probably cost him titles every time," Villeneuve said.
"Last year especially he was in a good position to win the championship with the best car on the grid before he crashed at home in Hockenheim.
"We know the rest: Hamilton took control from then on. Only if Vettel can chase away his demons will he win a fifth world title," Villeneuve added.