A former All-Star, Johnson made four appearances for Toledo after signing with Detroit, allowing three runs (two earned) in 4 2/3 innings.
The 31-year-old righty recorded 101 saves for Baltimore the previous two seasons. Oakland acquired him in a trade last December, but he struggled with the Athletics, posting a 7.14 earned run average in 38 games prior to being released on Aug. 1. Johnson signed with Detroit a few days later.
To make room for Johnson on the 25-man roster, the Tigers optioned pitcher Melvin Mercedes to Toledo. Pitcher Kevin Whelan was designated for assignment to clear room on the 40-man roster.