The 30-year old Honduras international arrives at Dick's Sporting Goods Park in exchange for midfielder Atiba Harris who heads to Santa Clara.
"Marvin is a dynamic attacking player with a lot of international experience, who can both create and score goals," said Rapids technical director Paul Bravo.
"We're eager to bring him into our squad and help him get settled in Colorado. We would also like to thank Atiba for his work here last year. He was a true professional and we wish him the best."
Saint Kitts and Nevis midfielder Harris played 29 times for the Quakes in 2013 following his move from Vancouver Whitecaps at the end of 2012.
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