An internal combustion engine for a hybrid vehicle includes an engine block, a flywheel, and a grounding clutch coupled to the block. The block defines a bore along a first longitudinal axis. The flywheel is rotatable about the axis and includes a spline. The spline has a first tooth and a second tooth spaced apart from the first tooth to define a gap therebetween. The clutch is configured for preventing rotation of the flywheel about the first axis and includes a locking pin. The pin is transitionable between a locked position in which the pin is disposed within the gap and abuts the first and second teeth such that the flywheel does not rotate, and an unlocked position in which the pin does not abut the first and second teeth such that the flywheel rotates. A hybrid vehicle is also disclosed.