A sprinkler assembly including a pressure regulator and a flow stop element combined in a single assembly. In one embodiment, the sprinkler includes a sprinkler body in fluid communication with a water supply to provide water to the sprinkler, a riser movably mounted in the sprinkler body and in fluid communication with the sprinkler body such that the riser rises up and out of the sprinkler body when water is provided to the sprinkler, a nozzle assembly mounted on a top end of the riser and in fluid communication with the riser; and a regulation element mounted in the riser and in contact with a portion of the nozzle assembly. The nozzle assembly holds the regulation member in an open position to allow flow of water to the nozzle assembly and to maintain a substantially constant water pressure in the nozzle assembly.