Spangenberg, 24, spent the 2015 season with the Revolution, serving as the third-string goalie behind Bobby Shuttleworth and Brad Knighton. The Missouri State product didn't see first team action with the Revs but did get playing time during a loan to the Richmond Kickers (USL).
Spangenberg was released at the end of 2015 but rejoined the club on trial in 2016. Although he didn't earn a contract, he did catch the eye of Puerto Rico FC executives, which led to his signing.
Spangenberg will compete with David Meves for the starting spot. Originally drafted by the Portland Timbers in 2013, Meves spent two seasons with the St.