A hybrid powertrain system includes first and second torque machines, a differential gear set including first, second and third elements, an output member, and first, second, and third selectable one-way clutches (SOWC). The first SOWC is configurable to prevent rotation of the third element of the differential gear set in a first rotational direction when controlled to a first activated state, and configurable to prevent rotation of the third element of the differential gear set in a second rotational direction opposite the first rotational direction when controlled to a second activated state. The first torque machine is coupled to the third element of the differential gear set only when the second SOWC is controlled to one of the activated states. And, the third element of the differential gear set is coupled to the input member only when the second and third SOWCs are each controlled to one of the activated states.