Thursday will see CONMEBOL World Cup qualifying leaders Brazil host rivals Argentina in Belo Horizonte.
The stakes are high for Argentina, who are five points adrift of Brazil in sixth after 10 matches, and Pratto heaped pressure on the hosts with five-time Ballon d’Or Messi back in the squad having missed the past three qualifiers due to a knee injury.
“They know that Leo is very tough. They are a little scared,” Pratto – based in Brazil with Atletico Mineiro – told Argentine newspaper Ole.
“Or maybe more than a little.”
While the 29-year-old Barcelona star was injured, Argentina lost to Paraguay and drew with Peru and Venezuela.
Brazil, meanwhile, have won four consecutive qualifiers.