Interim manager Ricardo Ferretti admitted Friday his views on coaching Mexico had changed as he prepares for the end of his brief stint in charge of "El Tri" in their Confederations Cup showdown with the United States.

The Brazilian-born coach once famously said he would rather work as a street cleaner rather than manage Mexico, ruling himself out of contention for one of the most demanding jobs in international football.

Yet Ferretti, the coach of Mexican giants UANL Tigres, agreed to serve as caretaker manager of the national side for four games after the sudden dismissal of Miguel Herrera in July, saying he owed a debt to his adopted homeland.

The main goal of the 61-year-old's temporary appointment was to secure victory in Saturday's playoff against the United States at the Pasadena Rose Bowl, where the winner will advance to the 2017 Confederations Cup in Russia.

But Ferretti revealed that win or lose on Saturday, he had warmed to international football during his fleeting tenure.

"To be honest with you it's been very surprising," Ferretti said.

"I had an idea of what the job would be like, but I have been very surprised.

"As human beings and players, these guys are the best of the best. I'm going to leave the position with a great level of thankfulness and satisfaction irrespective of what happens tomorrow in the match.

"Everything has been great. It's something I'm never going to forget for the rest of my life. I feel very grateful to have had the opportunity to work with the entire team."

Ferretti is one of the most respected coaches in Mexican football, managing Tigres to the final of the Copa Libertadores this season.

He reportedly turned down the opportunity of taking the Mexico job full-time, preferring instead to see out the remaining three years of his club contract with Tigres.

However he agreed to coach the Mexico side for four matches on an unpaid basis, telling ESPN it was "out of gratitude to Mexican football, which has given me so much."