Chile edged out Peru 1-0 in their Pacific 'clasico' on Monday to win Group C at the Copa America.
Both sides went into their group finale on four points, enough to see both sides into the quarter-finals.
But it was a largely turgid affair which Peruvian defender Aldo Corzo settled by deflecting into his own net in injury-time.
The win put the Chileans on seven points from their three games with the Peruvians on four.
Uruguay could now take second spot - and book a quarter-final meeting with Argentina - if they win the late match against Mexico, who are already on their way home after losing their opening two games.