Iannetta departs as the team's all-time leader among catchers in games played, runs, hits, homers, RBIs and walks.
The 36-year-old hit .222 with six homers in 52 games this season.
Originally selected by Colorado during the fourth round in 2004, Iannetta made his major league debut on Aug. 27, 2006. He played with Colorado until being dealt to the Los Angeles Angels in November 2011. He also suited up for Seattle and Arizona before returning to the Rockies last season.
In other moves, Colorado purchased the contract of catcher Dom Nunez from Triple-A Albuquerque. Nunez will make his major league debut Tuesday against Arizona.
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