Peru bounced back from their opening 4-0 defeat to Brazil to stun Colombia 2-1 thanks to a Yerry Mina own goal.
Sergio Pena gave Peru a first half lead but Miguel Borja equalized from the penalty spot early in the second period.
However, Mina inadvertently bundled the ball past goalkeeper David Ospina from a corner to hand Peru victory.
Colombia were in the ascendancy early on but Juan Cuadrado lashed over and Borja's shot was deflected inches past the post.
Peru took the lead on 17 minutes as Yoshimar Yotun took aim from almost 30 yards out to the left, and when his stunning shot came back off the far post, the ball fell kindly to Pena to drill home.
Colombia were given a lifeline early in the second half when Borja got in behind Peru's defense only to be brought down in the penalty area by a rash challenge from goalkeeper Pedro Gallese.
Borja made no mistake from 12 yards, sending Gallese, who was booked for his challenge, the wrong way on 53 minutes.
Yet 10 minutes later Peru were back in front as Colombia's giant centreback Mina deflected a Christian Cueva corner into his own net with his chest.