Brothers had been designated for assignment by Colorado on Nov. 20.
Cabrera recently completed his first professional season as a member of the Dominican Summer League Cubs, where he went 4-3 with a 2.34 ERA in 14 appearances, including seven starts.
Brothers, 27, began last season at Triple-A Albuquerque, where he went 5-2 with a 4.46 ERA. In two stints with the Rockies, he was 1-0 with a 1.74 ERA. He was originally drafted by the Rockies in the first round in 2009.
In parts of five seasons, he was 16-11 with a 3.42 ERA in 286 appearances with Colorado.