The German is within touching difference of his first title, holding a 12 pint lead over team mate Lewis Hamilton and Villeneuve, who won the 1997 championship, feels his consistency has been key this season.
"Lewis was perhaps a bit faster throughout the season, but he has also made more mistakes," Villeneuve told Auto Bild.
"Rosberg was more consistent," he said, comparing the German with Alain Prost.
"If Prost needed to win he risked more, if not he tried to get the position he needed," said Villeneuve.
"If his car has no technical faults and he makes it through the first corner, he has the championship in his pocket," he said.
Meanwhile, F1 supremo Bernie Ecclestone feels that this weekend could Rosberg's only chance of winning a championship.
"Rosberg must take this opportunity, otherwise it may never come again," he told Blick.
Bahrain International Circuit - Winter testing