A powertrain and an electromechanical apparatus are disclosed. A ring gear is attached to a first distal end of a crankshaft such that the ring gear and the crankshaft are rotatable in unison about a longitudinal axis. A motor-generator includes a motor/generator shaft being rotatable about a first axis spaced from the longitudinal axis. A starter mechanism includes a first starter gear coupleable to the motor/generator shaft and rotatable about a second axis spaced from the longitudinal axis. The first starter gear is movable along the second axis between a first position engaging the ring gear such that torque is transferred from the motor/generator shaft through the first starter gear and the ring gear to the crankshaft to start the engine, and a second position disengaged from the ring gear to rotatably disconnect the starter mechanism from the ring gear.