Once a mainstay in the Reds' bullpen, Masset resumed his career with Colorado in 2014 after he missed the previous two seasons due to an injured right shoulder.
According to the MLB.com transaction page, Miami has made four additional Minor League signings this month: infielder Scott Sizemore, outfielder Tyler Colvin, right-hander Salvador Sanchez and catcher Arturo Rodriguez. Rodriguez will report to Class A Advanced Jupiter.
Masset was 2-0 with a 5.80 ERA and 36 strikeouts against 24 walks over 45 innings with the Rockies in 2014.
With Cincinnati from 2009-11, the right-hander logged at least 70 innings during three straight seasons. Masset opened '08 with the White Sox, but he went to the Reds midseason as part of the Ken Griffey Jr. trade.
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter @JoeFrisaro. This story was not subject to the approval of Major League Baseball or its clubs.