The Pirates reassigned Heller to minor-league camp Sunday, Kevin Gorman of TribLive.com reports.
The 32-year-old holds a 3.06 ERA over 50 career relief appearances at the big-league level over parts of five seasons, but his resume wasn't enough to win him a spot in the Pirates' Opening Day bullpen. After missing much of the 2021 and 2022 seasons while recovering from arm injuries, Heller enjoyed good health in 2023, but control proved to be a concern for him at both the major-league and Triple-A levels. He'll likely need to string together some quality outings at Triple-A Indianapolis early on in the season to garner a look in Pittsburgh.