Marcelo Bielsa has resigned as coach of Argentina less than a month after steering the country to Olympic gold.
Bielsa has battled hard to prove his critics wrong
Bielsa, 49, blamed the rigours of the job for his decision to stand down.
"I realised that I didn't have the amount of energy which is absorbed by the various tasks involved in being coach of the team," said Bielsa.
Argentina crashed out of the 2002 World Cup in the first round, but reached the final of the Copa America last year as well as their Olympic triumph.
He added: "I've always tried to interpret the preferences of the Argentine supporters and satisfy them.
"To be coach of the national team brings passion, because it is one of the most important national teams in the world.
"I went through what all coaches go through and criticism is part of the job. Argentina have a group of players who are capable of producing a lot and you have to be up to the demands."
Bielsa said he had taken the decision to quit while Argentina were in a healthy position in their World Cup qualifying group.
"The decision began to take shape after we came back from Lima in the last game," he said.
"If our situation in the qualifiers had not been favourable, I would not have taken this decision. This seemed to me to be the ideal moment.
"We have consolidated a variation in the make-up of the squad, we have united two generations. It appears to me that part of the job, which was to bring together two generations, has been completed.
"The national team is on the right track."
Argentina Football Association president Julio Grondona denied that former Boca Juniors coach Carlos Bianchi had already been named as Bielsa's replacement.