Edinson Cavani scored the only goal in the final 10 minutes at the Maracana on Monday night to see Uruguay leapfrog Chile into top spot in Group A.
In the process, the two-time World Cup winners set up a 2019 Copa America quarter-final match against Peru, whilst Chile will have to take on Colombia.
Paris Saintt-Germain striker Cavani glanced in Jonathan Rodriguez’s cross in the 82nd minute to decide a closely-fought contest.
Luis Suarez had earlier missed Uruguay’s best chance of the first half, seeing a shot deflected wide with an unmarked teammate on his shoulder.
Defending champions Chile never really threatened Fernando Muslera’s goal greatly, having already booked their quarter-final appearance after their first two matches. However, Colombia promises to be a stern test as the Teicolours have already beaten Argentina and were the only nation to take maximum points in the group stage and have yet to concede a single goal.