Boca Juniors striker Carlos Tevez has said Lionel Messi is "a natural at being the best in the world."
Asked in interview by ESPN Argentina about Barcelona's Messi and Real Madrid's Cristiano Ronaldo, Tevez said: "Cristiano is totally different to Messi.
"When Leo was starting out, he didn't touch a gym. Cristiano was there in the morning, afternoon and evening, all the time.
"Leo was always with the ball, while Cristiano practiced set pieces all day long.
"Cristiano had to work and prepare himself to be the best, while for Leo it comes natural. Since he was a boy you could see him with a ball on his feet.
"Those are the greatest differences that I see between the two best players on the planet."
Tevez, who has played alongisde Messi for Argentina, believes he is in a league of his own.
"Messi plays another sport," the 33-year-old former West Ham, Manchester United and Manchester City player said.
"For Messi to score three goals [in any given game] is normal."
The 30-year-old Messi is his country's all-time leading scorer with 61 goals in 123 appearances and his hat trick against Ecuador secured their place at the World Cup.
Tevez said he believed the national team was in good hands with Jorge Sampaoli in charge.
"Sampaoli knows very well what he does in the national team," he said.
"In order to make history, you have to win the World Cup. It's not good enough just to reach a final. You don't see a coach that lost a final much on TV, people only remember titles."