Hosts Chile moved into the Copa America semi-final after Mauricio Isla’s late winner knocked nine-man holders Uruguay out of the tournament.
Chile dominated a bruising contest, Eduardo Vargas and Arturo Vidal both going close before Edinson Cavani was sent-off for a second yellow card.
Uruguay held out until the 82nd minute when Isla smashed home from 16 yards.
In the closing moments of an ugly game Uruguay defender Jorge Fucile was red carded for a second caution.
Chile will now face the winners of Friday’s match between Bolivia and Peru (00:30 BST) for a place in the final.
For Uruguay, their tournament ended in disgrace in a stormy game which saw six yellow cards in addition to two reds at Estadio Nacional in Santiago.