Martinez, inset right, kept his fourth clean sheet of the tournament in Saturday’s 1-0 win over Brazil at the Maracana Stadium, a result which ended Argentina’s 28-year wait to claim a major trophy.
Angel Di Maria’s first-half goal proved enough, with Martinez saving smartly from Richarlison and Gabriel Barbosa in the second period. His Villa team-mate, midfielder Douglas Luiz, was an unused substitute for Brazil.
Martinez, who only made his senior international debut last month, was later named goalkeeper of the tournament.
“There are no words to explain this moment,” he said.
“It was a dream I had since I was a child. I went to Arsenal at 16 or 17 years old. After many years of effort and courage I knew the dream would come.”
Victory capped a remarkable 12 months for Martinez, who won the FA Cup with Arsenal before joining Villa in a £20million deal and going on to claim a club-record equalling 15 clean sheets.
He was only installed as Argentina’s No.1 for the Copa America after Franco Armani tested positive for Covid-19 but went on to play a crucial role, saving three penalties in the semi-final shoot-out win over Colombia.
Martinez was hailed a “phenomenon” by Lionel Messi, for whom Saturday’s win ended his own wait to win a major tournament with Argentina.
The 34-year-old was mobbed by team-mates at the final whistle and Martinez said: “I said that I preferred that we win it (for Messi) before me. Today we could give it to him. It was what he wanted most in his life.”
Villa will step up efforts to bring in competition and cover for Martinez with Lovre Kalinic set to spend the season on loan at Hajduk Split.
The Croatia international has not played for Villa since February 2019 and his exit means Martinez and Jed Steer are the only senior keepers on the club’s books.