This marks the seventh straight season that there's been at least one playoff spot still to be clinched entering the final scheduled day of the season.
2008: The New York Mets and Milwaukee Brewers entered the final day tied for the NL wild card race. The Brewers won and the Mets lost giving Milwaukee the spot. The Twins entered the final Sunday with a half-game lead on the Chicago White Sox for the AL Central lead. Both teams won. The White Sox then won a make-up game on Monday to force a one-game playoff, then beat the Twins for the AL Central title.
2007: The possibility of a massive set of ties existed: Mets and Philadelphia Phillies were even in the NL East at 88-73; Padres were in second in the NL West at 89-72, and the Colorado Rockies were 88-73. The Phillies won and the Mets lost to give the Phillies the NL East. The Rockies won and the Padres lost, setting up a one-game playoff between the two for the wild card, which was won by the Rockies.
2006: The St. Louis Cardinals entered the final scheduled day with a 1½-game lead on the Houston Astros in the NL Central. Had they lost and the Astros won, they would have had to play a make-up game on Monday, setting up a potential tie for the division lead. Both teams lost, handing the NL Central title to the Cardinals, who would go on to win the World Series.
2005: The Astros entered the final day of the season with a one-game lead over the Phillies for the wild card spot. The Astros would clinch, with Roy Oswalt netting his 20th victory of the season, beating the Chicago Cubs.
2004: The Astros entered the final Sunday of the season with a one-game lead on the Giants for the wild card. The Astros beat the Rockies to clinch the wild card.