It is going to be a two-player committee.
Both fullbacks played about a dozen plays. Tukuafu's significant involvement was a bit of a surprise considering he was signed last week and he was mostly a defensive tackle when he was previously with the 49ers. He was cut in September.
Dixon was Miller's backup. Harbaugh said he likes having both players as an option. Dixon is athletic, and Tukuafu is essentially an extra offensive lineman at 6-foot-4, 293 pounds.