Guilmet was designated for assignment on July 21 to make room on the 40-man roster when outfielder Carl Crawford was activated from the 60-day disabled list.
The Dodgers claimed the 27-year-old relief pitcher off waivers from the rays on July 10. Guilmet allowed one run on two hits in three innings of work in his three games with Triple-A Oklahoma City, with one walk and one strikeout. He has seen time in the major leagues in each of the last three seasons with the Rays, Orioles and Indians.
In Milwaukee, Guilmet takes the active roster spot of old friend Jonathan Broxton, who was traded earlier in the day to the Cardinals in one of a billion deadline deals.
Guilmet is one of 43 different pitchers used by Oklahoma City this season.