When Major League Baseball instituted the dual-Wild Card system before the 2012 season, it was widely assumed that there would be years in which a cluster of clubs with identical records would require their own tournament of tiebreaker games merely to decide who advances to the one-and-done Wild Card postseason round.
To date, though, that's yet to happen. We've had just one tiebreaker game -- a 2013 tilt between the Rays and Rangers to decide the second American League Wild Card slot -- since this format was initiated. And we haven't had a division tiebreaker since the Twins and Tigers rumbled at the Metrodome back in 2009 to decide the AL Central winner.
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But one can never be too prepared, and this year we've got a wide assortment of tiebreaker possibilities to ponder in both leagues, including some truly wild ideas in the National League. The goal is to lay out the most realistic ones remaining and how they would be settled.
Scenario: Two teams tie for the division
The classic divisional push. There are several spots where this could happen, but let's use the Astros and A's as the example. If they were tie finish the year in a tie atop the AL West, they would play a one-game tiebreaker on Oct. 1. Home-field advantage would go to the club with the better head-to-head record* (that's the Astros). The winner of this game would advance to the AL Division Series round, while the loser would either head to the AL Wild Card Game or head home, depending on whether it qualifies for the Wild Card.
*Note that if the head-to-head matchup is a draw, home-field advantage in all scenarios listed below goes to the team with the better intradivision record, or failing that, the team with the better intraleague record.
Scenario: Three teams tie for the division
This possibility is alive in the NL West. Were the Cubs, Brewers and Cardinals to be deadlocked at season's end, they would receive an A, B or C designation. Club A would host Club B on Oct. 1, and the winner would host Club C the following day. The winner of that game would be the division champ.
Think of this almost like a draft, and the team with the "first pick" can choose the scenario it likes best. A team might rather play two games than one if it gets to host both, which is why a team might choose to be Club A over Club C. On the other hand, a team could choose Club C designation if it wants to rest a certain pitcher and take its chance in one winner-take-all game, even if it is on the road.
Selection order would be based on the head-to-head records (i.e., Cubs' combined winning percentage vs. Brewers and Cardinals, Brewers' combined winning percentage vs. Cubs and Cardinals, and Cardinals' combined winning percentage vs. Cubs and Brewers).
Also of important note here: If all three of these teams were tied not just for the division but for the second Wild Card spot, then the loser of the second game would be declared the Wild Card club.
Scenario: Two teams tie for best record in the league or Wild Card
This would not involve any extra games. If the Cubs and Dodgers, for example, were to win their divisions outright and finish tied for the best record in the NL, the team with the better head-to-head record (in this case, the Cubs) would get home-field advantage throughout the League Championship Series round.
As for the Wild Card, if, say, the Cardinals and Rockies were the only two clubs in NL Wild Card position at season's end and had identical records, they would not play an extra game to determine who gets home-field advantage in the Wild Card Game. It would go to the team with the better head-to-head record (the Cards won the season series, 5-2).
Scenario: Two teams tie for the second Wild Card spot
If, for example, the Cardinals and Rockies tied for the second NL Wild Card spot, they'd have to play each other Oct. 1 for the right to advance to the NL Wild Card Game. Home-field advantage would go to the team with the better head-to-head record (the Cardinals).
Scenario: Three teams tie for two Wild Card spots
If the Cardinals, Brewers and Rockies were tied, the three teams would choose/receive A, B and C designations. Club A would host Club B on Oct. 1 and the winner would host Club C on Oct. 2. Again, the three designations are decided by head-to-head records. (The Cardinals and Brewers still have series against each other this week, so it's too soon to say how this example would shake out.)
Scenario: Three teams tie for one Wild Card spot
Now we're talking. And this is still a distinct possibility in the NL.
In the three-team tie, we'd have to have the three teams choose/receive their A, B and C designations, with Club C traveling to face the winner of the game between Clubs A and B to determine who advances to the Wild Card Game.
Scenario: Two teams tie for the division, plus a tie with club outside division for a Wild Card spot
If the Rockies and Dodgers finished in a tie atop the NL West and a third club -- let's say the Brewers -- tied them for the second NL Wild Card spot, the following would happen: The Rockies and Dodgers would play a tiebreaker game Oct. 1 (at the home park of the club with the better head-to-head record). The winner is the division champ, and the loser would face the Brewers at Miller Park (in this scenario, MLB has determined that the team from the other division gets home field in the second tiebreaker game, regardless of the head-to-head record) the following day to determine the winner of the second Wild Card spot.
If it were a tie for the division and a tie with an outside club for two NL Wild Card spots, the scenario is the same as above, except this time the second game would be the NL Wild Card Game, with home-field advantage determined by the two-team tiebreaker system mentioned earlier.
Scenario: Two teams tie for the division, plus a tie with club outside division for two Wild Card spots
Same as above, except this time the second game (Brewers vs. loser of Rockies-Dodgers) would be the NL Wild Card Game, with home-field advantage determined by the two-team tiebreaker system mentioned earlier.
Scenario: Two teams tie for the division, plus a tie with two clubs outside the division for two Wild Card spots
Let's take the above and add a fourth team -- the Cardinals -- into the mix. Two games would take place Oct. 1 -- the Dodgers-Rockies game to determine the NL West winner and a game between the Cardinals and Brewers to determine who advances to the Wild Card round. The losers of those two games would then face each other Oct. 2 (with the same tiebreaker rules applied to determine home field) to decide who faces the winner of the Cardinals-Brewers game in the NL Wild Card Game on Oct. 3 (again, with the same previously stated home-field advantage rules applied).
Scenario: Three teams tie for the division, plus a tie with a club outside the division for one Wild Card spot
If it's the Cubs, Cardinals, Brewers and Rockies all knotted up, they would go to the A, B, C and D designations (Club D would be the club outside the division, so the Rockies). On Oct. 1, Club A would host Club B and Club C would host the Dodgers. It's too soon to know how the head-to-head matchups would finish or what designation clubs would choose, so let's randomly assign the Cubs as Club A, the Cardinals as Club B and the Brewers as Club C.
If the Rockies beat the Brewers, they would be declared the Wild Card club. The winner of the game between the Cubs and Cardinals would be declared the NL Central champion.
If the Brewers were to defeat the Rockies, the winner of the Cubs-Cardinals game would then host Milwaukee. The winner would be declared the division champ and the loser would be declared the Wild Card club.
Scenario: Three teams tie for the division, plus a tie with a club outside the division for two Wild Card spots
Same setup as above, except: If the Rockies beat the Brewers in the first "round," the loser of Cubs-Cardinals would host the Brewers to determine the second Wild Card club. Alternatively, if the Brewers beat the Rockies, they would face the winner of Cubs-Cardinals to determine the NL Central champion. The loser of that game would be declared one Wild Card club, while the loser of Cubs-Cardinals would host the Rockies to determine the other Wild Card club.
Scenario: The two World Series teams have the same regular-season record
In case you forgot, World Series home-field advantage is now tied to regular-season records. If the Cubs and Indians, for example, were to face each other in the World Series and had identical regular-season records, home field would go to the club with the better head-to-head record in 2018. In this case, that would be the Indians, who beat the Cubs three times in their four meetings this year. Had the clubs not met in Interleague Play, the second tiebreaker would be division record. If that were also a tie, the tiebreaker would be intraleague records (the NL club's record vs. NL teams and the AL team's record vs. AL teams).
Anthony Castrovince has been a reporter for MLB.com since 2004. Read his columns, listen to his podcast and follow him on Twitter at @Castrovince.