CONMEBOL took the decision after the mayor's office in Bogota announced neither team would be allowed to play at El Campin as a security measure to guard against swine flu, which originated in Mexico.

The confederation are currently in negotiations with Chile about hosting the two games and CONMEBOL spokesman Nelson Benitez said: "The matches between San Luis and Nacional and Guadalajara against Sao Paulo have been postponed for a week. The other six games will be played as scheduled."

San Luis were due to host Nacional next Wednesday and Guadalajara were set to meet Sao Paulo one day later.