Boca Juniors have been thrown out of the Copa Libertadores after some of the team's fans sprayed River Plate players with an irritant on Thursday.
Boca have also been fined US$200,000 (£127,000) and must play four home games behind closed doors.
Four River Plate players were taken to hospital following the half-time incident at Boca's Bombonera stadium.
The last 16 second-leg tie between the Argentine rivals in Buenos Aires was abandoned with the score at 0-0.
The River Plate medical team said the players were suffering inflammation of the cornea after the incident in Thursday's match and needed a few days to recover from their injuries.
South American football's governing body Conmebol handed River Plate a walkover to the quarter-finals of the competition, the continent's equivalent of the Champions League, where they will face Brazil's Cruzeiro.
Thursday's match was the third between the teams in 12 days - Boca Juniors beat River Plate 2-0 in the Primera Divison match at the Bombonera on 3 May, but River Plate won the first leg of the Copa Libertadores last-16 tie 1-0, four days later.
In addition to the fine and stadium closure, Boca fans will also be banned from four away games.
Football in Argentina has been blighted in recent years by violence. In December, footballer Franco Nieto, 33, died after being struck in the head following a match between regional club Tiro Federal and Chacarita Juniors.