The 29-year-old right-hander was with the Brewers on a minor league contract. He was released after Milwaukee's 7-0 loss on Sunday night to Oakland, when Perez retired the only batter he faced in the game.
Perez was 1-1 with a 2.70 ERA in 10 games in spring training with Milwaukee. He has 133 career saves, with most of them coming while with the Cleveland Indians from 2009-13.
Under baseball's collective bargaining agreement, the Brewers had until Tuesday to give Perez written notice he would be on the opening-day roster, pay a $100,000 retention bonus or release him.
If added to the 40-man roster, he would have received a one-year contract calling for a $1.5 million salary in the major leagues.