The AL East and AL West Division winners will be the top-two seeds in the American League playoff bracket.
But how that breaks down is still to be determined. The Toronto Blue Jays and New York Yankees are duking it out for the AL East title, while the Mariners have clinched the AL West but still could get the overall No. 1 seed.
The top-seeded team in each league gets home-field advantage through the ALCS.
And the AL East winner is a crucial spot because it earns a bye into the division series.
With two games left, Saturday and Sunday, here's how the tiebreakers will work for these three teams:
Who holds the Blue Jays-Yankees tiebreaker?
The Toronto Blue Jays hold the tiebreaker with the New York Yankees based on head-to-head record.
If Toronto matches New York's season record, it'll be the Blue Jays winning the AL East Division and forcing the Yanks to be a Wild Card team.
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Who holds the Blue Jays-Mariners tiebreaker?
The Toronto Blue Jays hold the tiebreaker with the Seattle Mariners based on head-to-head record.
If Toronto wins the AL East and has the same record as Seattle, it'll be the Blue Jays claiming the No. 1 seed and home-field advantage.
Who holds the Yankees-Mariners tiebreaker?
The New York Yankees hold the tiebreaker over the Seattle Mariners based on head-to-head record.
If the Yankees win the AL East and have the same record as Seattle, it'll be the Yanks claiming the AL's No. 1 seed and home-field advantage.
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