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The Copa Libertadores 1990 was the 31st edition of the Copa Libertadores, South America's premier international club football tournament organized by CONMEBOL. Olimpia won the 1990 edition after defeating Barcelona with a 3-1 aggregate in the finals. One of the players for Olimpia was legendary goalkeeperEver Hugo Almeida, who retired from professional football the following year.
The champions and runners-up of each football association were drawn into the same group along with another football association's participating teams. Only one club from Colombia competed as Atlético Nacional was champion of the 1989 Copa Libertadores. They entered the tournament in the Second round.
Note: The other two Colombian teams that qualified for the tournament withdrew due to logistical issues, as CONEMBOL banned Colombia from hosting matches due to threats made by drug lords to referees in the previous tournament in 1989, with the murder of one of them interrupting the league without a champion being declared. The champion, Atletico Nacional of Medellín, had a bye to the second round as the current champion, but had to play their home games in Chile for this tournament.
Olimpia had been drawn to face the third-placed team from Group 2, but that group was reduced to two teams after the withdrawal of Colombian teams.
Quarter-finals
Note: Second leg between Vasco da Gama and Atlético Nacional was a replay in Santiago (Chile). The original match ended with a victory by 2-0 for Atlético Nacional, but it was annulled following a protest by Vasco da Gama complaining of pressure on the referee by local drug lords.