The 1978 World Cup winner feels that the Barcelona star, though a "special case", will need backup if Argentina are to go all the way at this summer's tournament in Brazil
The former striker, who scored twice in the 1978 final when his country beat Netherlands 3-1, acknowledges that the Barcalona forward is "a special case" but says that his nation's other star men need to step up to the plate and ease the pressure on their talisman.
"You can put the players on the pitch but they always move and systems change. I think, though, that Messi has to be a special case and that the other nine outfield players should support him," Kempes told Fifa's official website.
"But one player on his own is not going to win you the World Cup. That's impossible.
"He can have an important part to play, no question, but there's no way he can win every game for you by himself."
Kempes admits that Argentina's defence might not be at the same level as their attack but insists that he has faith in coach Alejandro Sabella.
"Argentina have a chance to win it although there's a big difference between the front line and the back line," he remarked, "but Sabella has put his faith in these players, in the goalkeeper who's not playing for his club [Sergio Romero] and in the defenders and we should trust him."
Argentina are due to face Bosnia and Herzegovina, Iran and Nigeria in the group stage.