Delving Deeper: Studying Baseball's Wild-Card Team Using Probability

The modern era of professional baseball playoffs began in 1903, when the champions of the American League and the National League played the first World Series. Except for one year, 1904, this playoff system was maintained until 1969. Beginning in 1969, each of the two leagues in Major League Baseball (MLB) was divided into two divisions to accommodate the addition of extra teams in each league. From then through 1993, the two divisional champions in each league played against each other in an initial playoff round to determine which teams would go on to the World Series.