(baseball) A metric used to determine a team's required performance to make the playoffs.
The sum of one and the wins by one team and losses by an opponent necessary for the team to ensure the opponent cannot catch it in the standings by the end of the regular season. In Major League Baseball, with a regular season of 162 games, the magic number M is calculated as M = 163 - W1 - L2, in which W1 is the leading team's current win total, and L2 is the opponent's current loss total. A magic number of 0 indicates that the trailing team cannot catch the leading team.
By extension, the lowest such number that assures a team a playoff berth.