The Reds have designated Mike Costanzo for assignment, the team announced (on Twitter). The move creates room on the roster for Dioner Navarro.
Costanzo, 28, had one single and one walk in 21 plate appearances for Cincinnati this season, good for a .056/.095/.056 batting line. The infielder was involved in two high profile trades in 2007, first the Brad Lidge–Michael Bourn swap and then the Miguel Tejada–Luke Scott deal.