On November 17, 2016, Thielbar signed a minor league deal with the Miami Marlins. He was released on March 31, 2017. On May 27, 2017, Thielbar signed with St. Paul for the rest of the 2017 season. He was 2-1 with one save and a 2.01 ERA in 22.1 innings in which he struck out 23 batters.
