Definitely the GOAT. Joined the Celtics in 56-57 and they made the Finals 12 of the next 13 seasons, winning 11 times. He was the player-coach of the Celtics for the last 3 years of his career winning two titles. Otto Graham is the other guy in the running for GOAT, based purely on years played and wins. And of course Sam Jones played with Russell every year but Russell's rookie season however Jones was not a starter his first two seasons.