A Requiem for Team Entropy

Once upon a time, mid-September brought my annual check-in on the potential for end-of-season chaos in the playoff races via my Team Entropy series. With the new Collective Bargaining Agreement and the restructured postseason, however, Major League Baseball has done away with tiebreaker games and the scheduling mayhem that they could cause in favor of greed a larger inventory of playoff games. Along with the expansion of the playoff field from 10 teams to 12 and the Wild Card round from a pair of winner-take-all games to a quartet of three-game series, MLB did away with all winner-take-all regular season tiebreaker games. In the name of efficiency, we have no more Game 163s. Instead, ties will be decided by the excitement of… mathematics. Boooooooo!

The untangling of the often-complex scenarios by which those tiebreakers could come about was Team Entropy’s raison d’etre, though we were able to make do in 2020, when in the name of minimizing travel and keeping the schedule compact to accommodate an expanded field, MLB similarly opted to dispense with the on-field tiebreakers. That wasn’t nearly as much fun, but at the very least, it feels appropriate to sketch out what’s at stake while pouring one out in memory of what’s been lost.

As you’re probably aware by now, each league’s playoff field will consist of six teams, namely all three division winners plus three Wild Cards with the best records from among the remaining teams. The top two division winners by record get first-round byes, while the third division winner (no. 3 seed) plays host for all three games against the third-best Wild Card team (no. 6 seed) and the top Wild Card team (no. 4 seed) hosts all three games against the second-best Wild Card team (no. 5 seed).

There’s no re-seeding after that round; the 3/6 Wild Card winner plays the no. 2 seed while the 4/5 winner plays the no. 1 seed. This leaves open the possibility of a Wild Card contender facing a competitive quandary as it heads into the final weeks of the season: Try to set things up so as to face the weakest of the three division winners as the sixth seed, and then — if they advance — the second seed instead of the first seed rather than going for broke and trying to get the fourth seed and home-field advantage for the Wild Card series, only to advance and face the top seed in the Division Series. With just 1.5 games separating the Blue Jays, Rays, and Mariners top to bottom, with a potential paths through the Astros or Yankees looming in the Division Series, this isn’t some abstract hypothetical, either. (Yahoo Sports’ Zach Crizer explored the situation last week, while Baseball Prospectus’ Rob Mains took a look in August.)

As noted, whether it’s teams jockeying for seeding or merely to make the cut for the postseason, in the event that two or more teams finish with the same record, everything will be decided on paper (or pixel) rather than via more games. Like the five stages of grief, MLB has five stages of breaking the ties:

1. Head-to-head records. This is self-explanatory when it comes to two-team tiebreakers, and if they played an odd number of games against each other, which is currently the case if they’re in the same division, then no other steps will be necessary. If more than two teams are involved, then the team with the best combined winning percentage against the other teams in the tie wins the tiebreaker, and, if it’s still relevant, the remaining two teams are un-tied via head-to-head records and on down the line.
2. Intradivision records. This one is relevant only for two situations: multi-team scenarios where the teams all have the same head-to-head records within the group, or for two Wild Card teams in different divisions; in the latter case, there’s still a good chance they played seven games against each other instead of six.
3. Interdivision records, meaning records against the other two divisions in the same league. If there’s a tie between an AL East team and an AL West team, both of whom had the same intradivision records, this would pit the AL East team’s record against AL Central and AL West teams versus the AL West team’s record against AL Central and AL East teams.
4. Second-half of intraleague games. If a team has 20 interleague games, then this would be decided based on their winning percentage over the last 71 (half of 142) games against teams in their own league. And if that doesn’t work…
5. Second-half of intraleague games plus one… or more, as needed.. Under the above scenario, then this would be decided based on their winning percentage over the last 72 intraleague games, then 73, 74, 75… as many as it takes.

While the Dodgers have clinched the NL West and the Astros the AL West, three of the other divisions have margins of at least seven games at this writing, with their leaders having at least a 99.5% chance of holding on according to our Playoff Odds. The exception is the NL East, where the Mets lead the Braves by a game and a half, and where a first-round bye as the no. 2 seed is additionally at stake. Settling this one will be completely straightforward, as the Mets lead the season series 9-7 with three games in Atlanta left to play from September 30 to October 2; the Braves need a sweep if they’re to claim the tiebreaker. Beyond that, here’s the rest of the NL picture:

The Braves and Mets have both already clinched playoff spots, and they’re far enough ahead of the other three teams that there’s almost no chance of either of them winding up in a tie; the loser of that race will be the fourth seed. All of the remaining two-team tiebreakers, whether to determine the fifth and sixth seeds or the sixth seed and the hard-luck team, are clear-cut, as their respective season series have concluded. The Phillies have the upper hand on both the Padres and the Brewers, while the Brewers have the short end of the stick on both, and the Padres have the advantage on the Brewers but not the Phillies.

If the Padres, Phillies, and Brewers all wind up tied, the Phillies would get the fifth seed based on their 8-5 record against the other two, compared to the Padres’ 7-7 and the Brewers’ 5-8. The Padres would then claim the sixth seed based on their 4-3 season series advantage over the Brewers, and Milwaukee would be left wondering if it should have just held onto Josh Hader.

Over to the AL:

With all but one of the series among these teams involving an odd number of games, and with the only one that’s an even number not a split (Mariners over Orioles, 4-2), any two-team ties in the AL race will be settled by head-to-head records. As you can see, the Rays are particularly well set up in this regard, having clinched series victories over the Mariners and Orioles, and owning a two-game advantage over the Blue Jays with three more to play against them at Tropicana Field after Thursday night’s win.

If the Blue Jays, Rays, and Mariners were to all wind up tied, with the Orioles out of the picture, then based on their current records — that’s how I’m doing all of these scenarios, while noting that there are games remaining — the Rays would win the top seed on the basis of their 14-9 record against the other two teams, compared to Seattle’s 7-7 record and Toronto’s 9-14 record. Once the Rays are un-tied from the knot, the Mariners’ 5-2 advantage over the Blue Jays would slot the two teams into the fifth and sixth seeds, respectively. If the Blue Jays had won on Thursday night and then continued to sweep this weekend’s series, then all three teams would have .500 records within the group and the attention would turn to their intradivision records, in which case right now it’s the Rays with the best record. That door has been shut in our faces, however, and so we move on.

If the Orioles somehow surpass the Rays and wind up with the same record as both Toronto and Seattle, the Mariners would get the top seed on the basis of their 9-4 record against the other two teams. The fifth seed would hang in the balance pending the outcome of the three-game series between the Blue Jays and Orioles in Baltimore from October 3-5.

If the Orioles surpass the Mariners (sorry, Seattle fans) and tie with the Blue Jays and Rays, it’s Tampa Bay that would get the top seed based on their current 19-16 record against the other two teams; the Orioles are 17-18 and the Blue Jays 15-18, but what matters there is only who wins those two teams’ season series, as noted above. If it’s the Blue Jays who fall out of it (sorry, Canada) and the other three teams tie, Tampa Bay has the upper hand in that three-way tiebreaker by dint of their 15-11 record against the other two, where Seattle is 6-7 and Baltimore 11-14.

In the closest thing we’re likely to get in terms of logjams, if all four teams wind up tied, the Rays would get the nod as the top seed based on their 24-18 record against the other three teams. Both the Orioles (19-22) and Blue Jays (17-22) are below .500 within the group and have no chance to surpass the Rays, but the Mariners are 11-9 (.550) and could move past the Rays if Tampa Bay loses all three remaining games to Toronto to drop their winning percentage within the group to .533. Once that winner claims the no. 4 seed and is removed from the group, we go back to the three-team tiebreakers. If it’s Baltimore, Seattle, and Toronto remaining, the Mariners are the no. 5 seed on the basis of the aforementioned 9-4 record against the other two, and then it comes down to whoever wins the Baltimore/Toronto season series for the no. 6 seed. If it’s Baltimore, Tampa Bay, and Toronto remaining, it’s the Rays getting the no. 5 seed based on that 19-16 record, and again the outcome of that Baltimore/Toronto season series determining who plays on and who goes home.

Barring something that’s got less than a 1% chance of happening — the White Sox getting to 88 or 89 wins while some of the other AL contenders get bogged down in the September mire — that’s about it. The remaining regular season drama will center on the three pending series (Blue Jays-Rays, Blue Jays-Orioles, and Mets-Braves), and whatever bonus baseball out of it will be limited to extra-inning contests with the damn Manfred Man starting on second base. I don’t like it, and you don’t have to, either, but it’s what we’re left with.