Rasmus was designated for assignment by the Angels on Tuesday.
The Angels activated five pitchers off the 60-day DL, leaving no room on the 40-man roster for the 29-year-old. Rasmus battled a groin injury during the season, but even when he was healthy, he was only able to muster a 5.84 ERA across 19 appearances, although his major league experience could help him ascend back into the major league bullpen.