Sun was aboard a 42-foot Catalina sailboat taking part in a race hosted by a local yacht club that hit a channel marker buoy and became entangled shortly before 7 p.m., according to the U.S. Coast Guard.
Other boats had trouble reaching the damaged boat in the shallow water, but a U.S. Geological Survey boat that happened to be nearby pulled two people from the water and got them medical attention, Coast Guard officials said. The Coast Guard and Redwood City Fire Department also responded to the scene.
Sun succumbed to his injuries while the second person survived.
A total of five people were aboard the yacht when it crashed. The other three passengers were uninjured and eventually managed to free the boat from the buoy, according to the Coast Guard.
The Sequoia Yacht Club confirmed Wednesday night that the boat had been taking part in a race staged at the club, located at 441 Seaport Court in Redwood City.
The cause of the collision was under investigation. Fire officials said in statements on Twitter that the boat had sustained a broken mast in the crash.