I once read (I think it was from Bob Ryan) that in 21 winner take all games (2 NCAA tourneys, 1 Olympics, and NBA-best of 5 and best of 7) that Russell was 21-0 in those games.
Because I'm bored and poker'd out right now:
1955 NCAA: San Francisco 77, La Salle 63 (Russell MVP, KC Jones also on the team, La Salle was defending champ)
1956 NCAA: San Francisco 83, Iowa 71 (team was 29-0, undefeated)
1956 Olympics: USA 89, Soviet Union 55 (Russell Captain; the era was not so competitive, the semifinal went USA 101, Uruguay 38)
1957 Finals Game 7: Boston 125, St Louis 123 (2OT)
1959 ECF Game 7: Boston 130, Syracuse 125
1960 Finals Game 7: Boston 122, St Louis 103
1962 ECF Game 7: Boston 109, Phil. Warriors 107 (game was tied with 2 seconds left before a Sam Jones winner)
1962 Finals Game 7: Boston 110, LA Lakers 107 (OT) (an all-timer Russell theft game, his entire frontcourt fouled out,
the game was nuts)
1963 ECF Game 7: Boston 142, Cincinnati 131
1965 ECF Game 7: Boston 110, Phil. 76ers 109 (Havlicek stole the ball)
1966 ECSF Game 5: Boston 112, Cincinnati 103
1966 Finals Game 7: Boston 95, LA Lakers 93
1968 ECF Game 7: Boston 100, Phil. 76ers 96 (first-ever comeback from 3-1 down in a series; another all-timer Russell game)
1969 Finals Game 7: Boston 108, LA Lakers 106 (Lakers put balloons up in the forum prior to the game, enraging a worn-out Russell)
That's 14-0. I guess you could argue the other 4 (1955) and 3 (1956) NCAA games, plus the Olympic QF and SF (single-elim, prior rounds were round-robins), which would get you to 23.
Russell eliminated:
- 1958 NBA Finals: St Louis over Boston (4-2) (Russell missed games 4 and 5 with an injury)
- 1967 ECF: Phil. 76ers over Boston (4-1) (first year with Russell as player-coach)
He also only went 14-7 at USF as a sophomore.