Crunching the numbers on the AL three-way tie scenario
As play gets underway on the the final afternoon of the regular season, Team Entropy still has a chance at pulling out the dream scenario of a three-way tie between the Rays, Rangers and Indians for the AL wild card. That would necessitate a two-day tiebreaker scenario just to determine who plays in the wild-card game on Wednesday.
A rough back-of-the-envelope calculation based solely upon the contending teams' winning percentages (Texas and Tampa Bay both .559, Cleveland .565) and disregarding opponent records and home-field advantage yields a 13.6 percent chance of the three-way tie.
A more sophisticated calculation using the winning percentages of the two teams involved in each game via Bill James' Log5 formula (WPCT = .500 + A - B) — which is used in the Monte Carlo simulations that make up the Baseball Prospectus Playoff Odds — yields an 11.9 percent chance of the three-way tie.
Since the home team typically wins 54 percent of games, if you add 20 points of winning percentage for each home team and subtract 20 for eaach visitors, that gets you back to a 13.2 percent chance.
With the Rays jumping out to a 6-0 lead in the first inning and holding a 93 percent chance of winning through the third inning according to the FanGraphs Win Probability Added iPhone app, the odds of the three-way tie are up to 22 percent as play gets underway in Cleveland.
UPDATE 1: As of first pitch of the Rangers-Angels game, the Rays are up 7-0 on the Blue Jays through five innings (98 percent win probability) and the Indians are up 2-0 n the Twins through three innings (72 percent win probability), so the odds of the three-way tie are around 17 percent. As noted previously, if the three-way tie does happen, MLB has already announced that the Indians would host the Rays on Monday, with the loser traveling to Texas to play the Rangers on Tuesday.