Twice in the Broncos' last six games, that's been the pattern. It's not a matter of who's starting, although when you factor in Hillman's 103-yard performance in the Week 4 win over the Minnesota Vikings, three of the five 100-yard performances by Broncos running backs have come from the backup among the duo.
Hillman will start Sunday, but that doesn't really matter; Head Coach Gary Kubiak has indicated that he will ride the "hot hand" as each game progresses.
But neither back is bothered by the other starting.