Sean Lissemore signed a three-year contract extension with the Cowboys last September with thoughts of being a part of the team's future.
But that was before the Cowboys switched from 3-4 to the 4-3 defense in the off season.
Now, he's a member of the San Diego Chargers after the Cowboys traded him on Sunday for a seventh-round pick in the 2014 draft.
They claimed linebacker Kyle Bosworth off waivers from the Giants to fill his spot on 53-man roster.
Lissemore, an active end in the 3-4, proved to be a non factor as a tackle in the 4-3 throughout training camp the preseason _ a huge disappointment considering the depth concerns the team had because of injuries at the position.
Lissemore was passed on the depth chart Nick Hayden and Brandon Bass. Landon Cohen, who signed with the team after the start of training camp, also proved to be more active in practice and games.
The move with Bosworth, just like the decision to trade for linebacker Edgar Jones from the Chiefs on Saturday, was all about upgrading the special teams.
The Cowboys have struggled on special teams throughout the preseason, especially on kickoff and punt coverage.
Bosworth spent the first three years of his career as a special teams performer with the Jacksonville Jaguars. He has 15 career tackles on special teams.
Bosworth played in college at UCLA and is the nephew of former Oklahoma star Brian Bosworth.