Baltimore Orioles right-hander Dean Kremer was activated from the 15-day injured list after recovering from a right triceps strain and is scheduled to start against the host Seattle Mariners on Wednesday.
In a corresponding move, the Orioles optioned left-hander Nick Vespi to Triple-A Norfolk.
Kremer, 28, last pitched on May 20 before going on the IL for a team that already lost three starting pitchers to season-ending injuries: Kyle Bradish, John Means and Tyler Wells. He was 3-4 with a 4.32 ERA, 18 walks and 49 strikeouts in 50 innings over nine starts.
In three rehabilitation starts at Norfolk, Kremer was 0-1 with an 11.42 ERA, four walks and nine strikeouts in 8 2/3 innings. He has a 25-24 record in five with the Orioles, with a 4.35 ERA in 420 1/3 innings over 80 appearances (79 starts).
Vespi, 28, has a 3.18 ERA, two walks and seven strikeouts in 11 1/3 innings over 10 relief appearances with Baltimore this season.