Right-hander Juan Sandoval, who began the year with the Biscuits, is returning to the team.
Sandoval has been demoted from Triple-A Durham, where he was 1-1 with a 3.79 ERA in 11 appearances.
The 32-year-old had 11 saves and a 3.14 ERA in 22 games with the Biscuits at the start of the year. He and the just-promoted C.J. Riefenhauser are in a group that is tied for third in the Southern League with 11 saves.