It took just 14 minutes for Abubakar to give Colorado the lead, using an assist from Ronan to find the net for the first time this season.
Former Galaxy forward Kévin Cabral stretched the lead to 2-0 when he took passes from Diego Rubio and Ronan in the 65th minute and scored for the second time this season. Ronan picked up his third assist in the 81st minute on Jonathan Lewis’ first goal of the season.
The Galaxy avoided a shutout on an unassisted goal by Preston Judd — his first — in the 89th minute.
The Galaxy (1-6-3) are off to their worst start since the 1999 season. They wound up beating Colorado in the Western Conference semifinals that season before losing 2-0 to D.C. United in the MLS Cup final.
Colorado (2-3-6) improved to 7-1-2 in its last 10 games against the Galaxy. The Galaxy’s only win was a 4-1 victory in September.
The Galaxy had advantages of 17-9 in shots and 7-5 in shots on target.
William Yarbrough finished with six saves for the Rapids. Jonathan Klinsmann turned away two shots for the Galaxy.
The Rapids were coming off a scoreless draw with the Vancouver Whitecaps. Colorado has played three scoreless draws this season after just two 0-0 decisions last season.
Colorado returns home to face the Philadelphia Union next Saturday. The Galaxy will host the San Jose Earthquakes on Sunday.