The reason why the Lakers and the Celtics are the biggest rivals in the NBA is because ever since 1959 they had their first encounter in the Finals. These two teams dominated in the in the 60s, the 80s , and the late 2000s. They faced each other six times in the 60s, three times in the 80s, and 2 times in the late 2000s. The Los Angeles Lakers have won 11 championships and the Minneapolis Lakers have won 5.