Allen will start at shortstop and bat ninth in Sunday's game against the Royals.
Allen will start at shortstop for the fifth time in six games despite going an unremarkable 2-for-12 with four strikeouts and one walk since being called up from Triple-A Las Vegas on Tuesday. He's poised to serve as Oakland's top option at the position while Aledmys Diaz (hamstring) is on the 10-day injured list.