Cavanaugh will start at catcher and bat ninth in Friday's game versus the Rockies.
The Giants have faced five right-handed pitchers since Cavanaugh's promotion last week, and the lefty-swinging catcher has started all of them. Righty hitter Eric Haase has started both contests against lefties during that span, and it appears the two backstops will form a strict platoon while Daniel Susac (back) is shelved.