In 1967, both leagues voted to add 2 more teams each, to bring the league total to 24 teams, which started in 1969. Divisional play also began, with each league dividing into East and West division, creating another round of playoff games to decide the pennant winners. 

In 2012, the league began Wildcard play, adding 2 more teams to the playoff mix. When you select a season after 2011, it will include 12 teams instead of just the Top 10.