Basketball: 11 NBA championships. The rise of collective bargaining and free agency means athletes now rarely spend their whole career with just one team. In the 1950s and ’60s, long-term contracts kept players tied to their team. Of course, there were also only 10 teams in the NBA in 1957, when Russell won the first of 11 titles with the Boston Celtics. Russell alone has more championships than all but nine current NBA teams.