Messi hurt himself in the 64th minute when he ran following the ball and then fell over, making no contact with other players.
The 37-year-old lay down for several minutes in obvious pain. After he was helped to get back on his feet, he immediately took off his right shoe.
Television images later showed a crying Messi on the bench and a swollen ankle.
The 37-year-old was later in a better mood, clapping his hands and laughing, and in the end even got to lift the victory trophy following the 1-0 victory over Colombia.
– We managed to win for him and give him joy, said Di Maria, according to AP, following Messi’s 39th and likely last game in the South American championship.
Messi has struggled with a leg injury throughout the championship and missed one match in the group stage.
The final victory gave Argentina its 16th Copa América title.