Mathisen was designated for assignment Tuesday, Adam Berry of MLB.com reports.
EDGE Analysis
Mathisen was acquired from Arizona on May 16 but failed to crack Tampa Bay's 26-man roster during just over a month with the organization. With top prospect Wander Franco being added to the 26-man and 40-man rosters Tuesday, Mathisen found himself as the outcast on the 40-man. Mathisen could attract interest on the waiver wire from teams searching for infield depth but is highly unlikely to find a major role with a big-league club anytime soon.