Martinez made his most recent appearance as a reliever in Saturday's 2-1 loss to the Orioles, striking out two and allowing no hits and one walk over two scoreless innings.
Martinez's prior two appearances came as a starter, but he moved back to the bullpen over the weekend in anticipation of Frankie Montas' (forearm) return to the rotation. With the Reds officially activating Montas from the 15-day injured list to start Tuesday's game against the Diamondbacks, Martinez should stick in the bullpen moving forward until one of Cincinnati's five starters succumbs to another injury.