[1] Rivas was a member of the Argentina Davis Cup squad for ties in Rome in 1983 and Atlanta in 1984, but didn't feature in either.

[1] During his professional career his ranking peaked at 116 in 1985, a year in which he made the round of 16 at the WCT Tournament of Champions in Forest Hills.

In 1989 he made the quarter-finals of a Grand Prix tournament, the Rio de Janeiro Open, and beat Petr Korda at a Challenger event in Clermont-Ferrand.

[5][6] Between 2006 and 2009 he was vice-captain of the Canadian Davis Cup team, working with Frank Dancevic, Daniel Nestor and Frederic Niemeyer.

Now living in Florida, Rivas runs the Grita Tennis Academy in Palm Beach County.