Dotel, who turns 37 in November, packed his belongings and walked down the hallway to join his new club in the visitors' clubhouse.
The right-hander was acquired by the Dodgers from the Pirates for James McDonald and Andrew Lambo in a July 31 Trade Deadline deal. He was 3-3 with 22 saves and a 3.99 ERA in 60 games overall, and 1-1 with a 3.38 ERA in 18 games with Los Angeles.
Dotel will not be eligible to pitch for the Rockies in the postseason.
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.