Former Seattle Supersonics guard Donald "Slick" Watts has died at 73, his son announced on social media. Watts, an undrafted free agent in 1973, emerged as a fan favorite in the Pacific Northwest due to his stellar play, signature crooked headbands and frequent presence around the Seattle sports scene.

Donald 'Slick' Watts, a fan favorite for the Seattle SuperSonics and later a beloved teacher and coach in Seattle, has died. He was 73.

Donald "Slick" Watts died on Saturday, March 15. The Seattle Supersonics fixture was 73. Here's what we know about his cause of death.