William Yarbrough made four saves to keep his second consecutive clean sheet for Colorado, who are unbeaten in 18 consecutive home regular-season matches dating back to early last season.
Lucas Esteves left midway through the second half with what appeared to be a left hamstring injury, after providing the diagonal pass on Rubio’s opener.
Kansas City were also forced into an injury substitution, with Peter Vermes sending in midfielder Cameron Duke to replace Felipe Hernandez after 26 minutes.
They’ve now lost four straight on the road in MLS, a streak dating back to a 2-1 defeat in Minnesota last Halloween Night.
