The Brewers added Topa to their 60-man roster pool Tuesday.
He'll assume the 60-man spot of reliever Mike Morin, who was claimed off waivers by the Marlins earlier in the day. Topa, who posted a 2.63 ERA over 24 innings in relief at Double-A Biloxi in 2019, will report to the Brewers' alternate training site in Appleton.