Sinjin already was the best beach volleyball player in the world when this episode aired. I was playing at the time and I remember the beach being abuzz because Sinjin was on Magnum!James J. Walters wrote:
I also just found out recently that the actor playing Marcus, Magnum's volleyball partner who gets killed, is none other than Sinjin Smith! Sinjin will later become one of the biggest names in (beach) volleyball! In the episode, he is credited as St. John Smith, which threw me off.
More trivia for you... On the other side of the net is Sinjin's brother Andrew Smith, nowhere near as good a player as Sinjin but he did win a few opens in his day. He was also a Ralph Lauren model. The fourth player I believe is Jon Anderson who was Hawaii's best player at the time. They were playing on the Outrigger Canoe Club court and it looks like they were really playing a game and not just staging something for the camera - I'm sure Selleck insisted, after all, it's not everyday you get to partner with Sinjin Smith! Probably also why they showed stills from the game during the credits.