Colombian boost for Rice
The former Irish international was three-over par at the turn following a double bogey seven at the 551-yard 18th at Bogota Country Club.
But he stormed home in 32, despite a bogey at his final hole that took some of the gloss off birdies at the third, sixth, seventh and eighth.
Making his first Challenge Rice appearance of the season, Rice is just five shots behind leader Didier De Vooght of Belgium, who hit a five-under par 66 for a one stroke lead over Dutchmen Wil Besseling and Inder Van Weerelt (as well as Paraguay's Marco Ruiz and England's James Morrison.
Birr's Justin Kehoe and Ballyclare's Gareth Maybin fired one over par 72s but Michael Hoey's struggles continued as he opened with a seven over par 78.