If Boston and Oakland tie for the best record in the American League, Oakland wins the tiebreaker in any scenario, although it might go to the fourth tiebreaker.. See the note at the end of this post for why.
Detroit lost in extra innings, and the Athletics victory brings the ALDS home field magic number to 2. Boston was idle, and the ALCS home field magic number is 6. The Athletics have 5 games remaining: 2 @ LAA and 3 @ SEA.
Optimal results for the Athletics for Tuesday (all times Pacific):
- 5:10 PM - Minnesota defeats Detroit (ALDS Home Field = 2)
- 5:40 PM - Colorado defeats Boston (ALCS Home Field = 6)
- 7:05 PM - Oakland defeats Los Angeles (American)
- The Athletics would clinch home field for the ALDS.
- The magic number for best record in the American league would be 4, Boston and Oakland each having 4 to play.
Magic Number = 163 - A's wins (94) - OppL - 1 if tie breaks to Oakland
ALCS Home Field Advantage
- 6 for a tie = BOS (Idle; 2 @ COL, 3 @ BAL) (Any tie breaks to the A's*: 163 - 94 OAK wins - 62 BOS losses - 1 tiebreaker advantage)
ALDS Home Field Advantage
- 2 for a tie = DET (L @ MIN; 2 @ MIN, 3 @ MIA) (A's won season series: 163 - 94 OAK wins - 66 DET losses - 1 tiebreaker advantage)
*Tiebreaker with Boston. A tie would be broken in favor of Oakland as follows:
- Oakland and Boston tied the season series 3-3.
- Better intradivision record: OAK is 42-29 with 5 to play, BOS is 43-30 with 3 to play. The second tiebreaker magic number is 5. Because the only way for the primary magic number to move and this second tiebreaker magic number to not move is Boston losing both games to Colorado, the other 4 games to force a tie would reduce this magic number to 1 at worst, requiring resort to the third tiebreaker. All other scenarios ending in a tie would mean Oakland wins this tiebreaker.
- Better record in whole-season intraleague games (see UPDATE 2, below): OAK is 81-56 with 5 AL games remaining. BOS is 82-57 with 3 AL games remaining. The third tiebreaker magic number is 5. Because this number is the same and is affected in the same way as the intradivision magic number is, this can also end in a tie at worst if Boston loses both games to Colorado. All other scenarios ending in an overall tie would mean Oakland wins this tiebreaker.
- Better record in the last half of intraleague games: There are 142 intraleague games, meaning we look to the final 71 games. OAK is 42-24 with 5 AL games remaining. BOS is 40-28 with 3 AL games remaining. The fourth tiebreaker magic number is 2. Because a tie record necessarily requires at least 4 Oakland wins and Boston losses to American League teams, this tiebreaker always breaks to Oakland.
UPDATE: I desperately want to help Susan Slusser end the barrage of tweets going her way about the tiebreaker.
To recap, for about the 20th time, the A's hold the head-to-head tiebreaker with the Tigers but they tied head to head with Boston.— Susan Slusser (@susanslusser) September 24, 2013
@RattoCSN Don't get me started. Grrrrrrrr. Every day!! And I keep putting it in the paper and the blog!! Sheesh.— Susan Slusser (@susanslusser) September 24, 2013
The only scenario I haven't discussed is the event of a three-team tie with Boston and Detroit. We'll need the head-to-head records:
- OAK: vs DET (4-3), vs BOS (3-3)
- DET: vs OAK (3-4), vs BOS (4-3)
- BOS: vs OAK (3-3), vs DET (3-4)
So the three clubs do not have identical records against one another, and no club has a better record than the other two, and no two have a better record than the other one. Therefore, follow this procedure:
- The Clubs will be ranked by their overall winning percentage amongst the other Clubs combined. The Club with the highest overall winning percentage in that group chooses its designation, followed by the team with the next highest overall winning percentage. Oakland is 7-6, Detroit is 7-7, and Boston is 6-7. Oakland is the #1 seed. And Detroit would have home field advantage over Boston.
According to MLB, confirmed by #Athletics asst. GM David Forst, third tiebreaker for home-field advantage is now OVERALL intraleague record.— Susan Slusser (@susanslusser) September 24, 2013
Susan Slusser reports that Major League Baseball, confirmed by Assistant Athletics General Manager David Forst, has informed her that the tiebreaker criteria for settling ties changed after Houston moved to the American League, given each league fifteen teams each. The third tiebreaker is now whole-season intraleague record, and the fourth tiebreaker is second-half intraleague record. The above post has been edited to reflected these changes, but the result remains the same. Oakland can do no worse than tie the first three tiebreakers, and will always win the fourth tiebreaker in the event of an overall record tie.