Tiebreaker Possibilities
If the Giants, Cubs and Astros finish in a threeway tie, they would be seeded 1-2-3 based on head-to-head play. So that would make the Giants the No. 1 seed. It would be their choice whether to play one game or two. If they choose to play once:
# Cubs (No. 2 seed) play Astros (No. 3) -- in Chicago.
# The winner hosts the Giants the next day.
If the Giants choose to play two games (unlikely):
# They play the Astros in San Francisco.
# If they win, they play the Cubs the next day in San Francisco.
# If they lose, the Astros and Cubs play in Houston.
Two-way ties:
# If the Giants finish in a two-way tie with anybody, the game will be played in San Francisco.
# If the Cubs and Astros tie for the wild card, they would play in Houston.
If the Giants, Dodgers, Cubs and Astros finish with the same record, the Giants and Dodgers will play for the West. The loser then goes into the same three-way tiebreaker format to decide the wild card.