When I was like 10 years old, I got to go to Kevin McHale's basketball camp at Ocean Edge on the Cape. Kevin had invited a series of NBA players and coaches. A young Ron Harper did a little dunk competition on his own, Jerry Sichting taught shooting, Kevin even made an appearance later in the week (my sister helped to babysit his kids, apparently he was a really, really nice guy even back then).
Anyway, what's stuck with me from that week is that Red Auerbach was there, and right next to him was Doc Rivers. My coach that week - Flip Saunders. So this makes sense.