The last of the 10 Major League Baseball postseason spots were not handed out until the end of the 162nd regular-season game Sunday.
The Boston Red Sox and New York Yankees clinched the two American League wild-card spots to set up a head-to-head matchup Tuesday.
The AL Wild Card Game kicks off what is expected to be a wild month of postseason baseball.
Over in the National League, two of the league's most storied franchises will go head-to-head in its Wild Card Game.
The Los Angeles Dodgers failed to catch the San Francisco Giants in the NL West race, so they will take on the red-hot St. Louis Cardinals on Wednesday.
One playoff matchup in each league is already set from the second- and third-placed division winners. The No. 1 seed in each league awaits the wild-card winner in the divisional series.
MLB Playoff Format
The wild-card games Tuesday and Wednesday are winner-takes-all affairs.
Boston and New York will face off at Fenway Park on Tuesday. The winner of that contest takes on the Tampa Bay Rays in the ALDS. The Red Sox won the regular-season series 10-9, but the Yankees earned a sweep on their most recent trip to Fenway Park.
The Los Angeles-St. Louis victor from Wednesday's NL Wild Card Game heads to San Francisco to take on the Giants in the NLDS. Los Angeles went 4-3 versus St. Louis in the regular season, and the two sides split a four-game series at Dodger Stadium from September 6-9.
If the Dodgers win, it would set up one of the most anticipated NLDS matchups of all time against the Giants. The two were involved in the NL West race until the final day of the regular season and produced the two highest win totals in baseball.
The divisional series has a five-game format.
The higher-seeded team in each matchup hosts Games 1, 2 and 5, while the lower-seeded team is at home for Games 3 and 4.
For example, the Atlanta Braves and the Chicago White Sox had the worst records of the division winners in their respective leagues, so they will begin the postseason on the road.
Atlanta heads to Wisconsin to take on the Milwaukee Brewers. The teams split six regular-season games. Their most recent matchup was August 1 when Atlanta was reshuffling its order after a frenetic trade deadline that brought it Jorge Soler, Adam Duvall, Eddie Rosario and Joc Pederson.
In the AL, the White Sox head to Houston to take on the Astros. Houston won five of the seven games between the division winners. The last of those matchups took place July 18.
San Francisco and the Tampa Bay Rays earned the No. 1 seeds in their leagues. They have home-field advantage until they are eliminated. The Giants and Rays should have the edge in Game 1 of their respective series because they will be at home and have two extra days of rest with which to organize their pitching staffs.
The AL and NL Wild Card Game winners will be without their aces for the first two games of the divisional series. Gerrit Cole, Nathan Eovaldi, Max Scherzer and Adam Wainwright could come back for Game 3 of the ALDS or NLDS depending on how far they go Tuesday and Wednesday.
The winners of the divisional series will move on to the championship series round. The ALCS, NLCS and World Series are all seven-game series.