Breaston was set to make $3.8 million in 2013, the third year of a five-year contract Breaston signed in 2011. Breaston had the worst year of his career in 2012, catching just seven passes for 74 yards, appearing in only nine games. Breaston was left inactive toward the end of the season, despite reportedly being healthy.
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Breatson, who turns 30 in August, should be able to latch on with another team looking for wide receiver depth.
In two years with the Chiefs, Breaston appeared in 17 games, catching 68 passes for 859 yards and two touchdowns.
Boss was due $2.4 million in 2013 -- the second year of a three-year contract signed in 2012. Boss appeared in just two games for the Chiefs before suffering a concussion that prematurely ended his season. Boss finished the season with three catches for 65 yards and a touchdown.
Like Breaston, Boss should generate a fair amount of interest on the open market for teams looking for tight end depth.