This Monday, against the backdrop of the Mookie Betts trade, MLB dropped a bombshell. As Joel Sherman reported, the league is seriously considering expanding the playoff field starting in 2022. The new proposal, a 14-team field with an extra round and a bye, would radically alter the shape of the playoffs, so let’s walk through it and consider the ramifications.

The format would be significantly more complicated than the current one. The best team in each league would receive a bye, while the other six teams would face off in a best-of-three first round. That doesn’t necessarily sound groundbreaking, but there’s some fancy stuff going on behind the scenes. The division winner with the second-best record would get to pick which of the three worst Wild Card teams they’d like to play. The remaining division winner would pick another of those three, and the best Wild Card team would play the remaining team in the group.

The first round would be three games, all played at one park. From there, it would be business as usual: a five-game divisional round with four teams per league, two seven-game championship series, and the World Series.

The league told Sherman what they’re looking for with this new format. They want to drum up interest in baseball among borderline viewers while selling networks more playoff games. The league also hopes that more teams in the playoffs would drive attendance boosts during the regular season. Sherman discussed playoff expansion as a way to counteract tanking, though it’s unclear whether this was a league talking point.

We’ll come back to the effect on viewership, but I’m more interested in the competitive ramifications. For the best team in each league, there will be small positive change. They’ll play worse teams on average, and those teams will be less rested. But for the most part, it’s business as usual; home field advantage and three playoff rounds.

On the other hand, it becomes far less valuable to win your division without winning the league overall. You’ll get to choose your opponent, but that’s not particularly valuable. The spread between the fifth-best and seventh-best teams in the league will rarely be very wide. And instead of advancing to the divisional round, you’ll play a three-game series that could eliminate you from the playoffs.

Those eliminations would happen more often than you think. In a scenario where the home team projects to win a game at a neutral site 57% of the time, that increases their odds of winning the series to roughly 66%. Not a coin flip, but also not a gimme.

Meanwhile, it’s no great shakes to be that seventh team. It’s better than not making the playoffs, obviously, but a one-in-three chance of winning a first-round series, with the reward being a trip to play a five-game series against another better team? It’s hardly a compelling package.

That’s not to say it’s meaningless. I built a generic playoff field, with a spread of true talent winning percentages, and then simulated a million playoffs in the current system, taking into account home field advantage:

World Series Odds, Current System Seed Win% Win WC Win DS Win CS Win WS 1 0.625 – 63.1% 39.2% 22.6% 2 0.590 – 58.0% 27.2% 13.6% 3 0.555 – 42.0% 16.5% 6.5% 4 0.575 56.5% 22.0% 10.7% 4.8% 5 0.550 43.5% 15.0% 6.5% 2.5% 6 0.525 – 0.0% 0.0% 0.0% 7 0.510 – 0.0% 0.0% 0.0%

In the current system, the best team has the best shot, and the division winners all do well, even though the worst division winner isn’t as good of a team as the first Wild Card. Next, here’s the new format, or at least my best guess at it, as the seeding and re-seeding hasn’t been explained:

World Series Odds, Proposed System Seed Win% Win WC Win DS Win CS Win WS 1 0.625 – 63.0% 41.3% 24.3% 2 0.590 67.7% 40.7% 19.0% 9.5% 3 0.555 63.4% 30.3% 11.9% 4.9% 4 0.575 59.8% 23.2% 12.1% 5.6% 5 0.550 40.2% 13.8% 6.5% 2.6% 6 0.525 36.6% 15.4% 5.1% 1.8% 7 0.510 32.3% 13.6% 4.1% 1.3%

These extra teams are largely for show. The sixth and seventh teams combine to win the World Series 3.1% of the time. This is only one league, of course, but that comes out to around 6% total World Series odds for the scrub teams. Not only that, but imagine the plight of a team on the bubble of qualifying for these new playoffs.

Should you go all-out to secure the seventh seed? You have only a 32% chance of playing a home game in the playoffs, nevermind reaching the championship series or World Series. And what if you improve your team by a further 2 1/2 wins, which would make you the sixth seed in this scenario? You’re still only at about one-in-three odds to host a playoff game and still less than 2% to win the World Series.

The sixth team is in a similar bind. If they get worse by 2 1/2 wins, it hardly matters: their chances of hosting a playoff game fall from 36.6% to 32.3%. On the other hand, gaining four wins to become the fifth seed isn’t all that useful. Your odds of hosting a playoff game are still only 40%, and your World Series odds are under 3%.

There are problems at the top end as well. Being the second-best team in the league is far less rewarding in the new system. Your playoff journey ends in the Wild Card round a full third of the time, which does a number on overall World Series odds.

In our current system, going from a .550 true talent team to a .590 true talent team is great. The .550 team will either be the worst division winner or a Wild Card. Splitting the difference between those two, that gives the team a 4.5% chance of winning the World Series. Upgrade by 6 1/2 wins to be a .590 winning percentage team, and your odds rise to 13.6%, a 9% gain.

Add those same 6 1/2 wins in the proposed system, and you move from roughly a 3.8% chance of winning to a 9.5% chance. The same 6 1/2 win upgrade is worth less than 6% of a World Series title rather than 9%. Baseball isn’t short of owners looking for excuses not to upgrade their team, and this structure heavily disincentivizes marginal improvements.

Consider this year’s AL: the Yankees signed Gerrit Cole to try to pass the Astros. They were going after the top overall seed, to be sure. But there’s a valuable fallback. Being the best team in the league is great, but adding talent and being the second-best team in the league still gives you a good chance at reaching the World Series.

In the new system, being second-best is just okay. If there’s a clear best team, the cold financial calculus of dollars and championship probability will tell whichever team is second-best to avoid spending too much to chase. It might tell them to downgrade! Unless you can make yourself a clear favorite, you’re spending without a commensurate upgrade in your odds.

When you expand the playoff field significantly and make the first round more random, you’re flattening everyone’s incentives. The last two teams to sneak into the playoffs are tremendously unlikely to remain standing at the end, but baseball being what it is, they stand a decent shot of knocking off a division winner before succumbing to gravity.

I won’t claim to know teams’ exact reactions to these rules. Perhaps there are teams who would compete for a three-game playoff stint, even at an opponent’s park. If you’re projected to go 80-82, maybe it’s worth trying to go 83-79 and bank that sweet playoff berth, with its attendant banners and commemorative T-shirts.

Perhaps there are teams out there who would still try to win 95 games, even knowing how little value the wins from 85 to 95 have, simply because they enjoy building a good baseball team. The recent state of baseball would tell you that’s unlikely, but I won’t rule it out.

There’s no question that this new structure would lower incentives for already-good teams to improve themselves. Thus, the only question that remains is the effect on viewership and playoff chases. The effect on playoff chases is likely to be minimal; instead of races for the second Wild Card spot, we’ll have races for the fourth Wild Card spot.

That will tend to add more teams to the mix, but there’s a big countervailing effect. The race for division titles will be hugely deadened. This past year, the Cardinals, Brewers, and Cubs came into the last week of the year with the NL Central up for grabs. It was a huge prize; win the division, and you could face the Braves in the NLDS. Second prize was far worse — a date with Max Scherzer in DC. Third prize is you’re fired. Or, well, you miss the playoffs.

Under the new system, all three teams would be likely to make the playoffs (I know the Cubs completely collapsed and would have missed the playoffs, but that’s not the point). Meanwhile, winning your division is a marginal upgrade if your talent level doesn’t change. The stakes will be lower in every division race, and even the stakes at the seventh-place bubble won’t be huge due to the sheer unlikeliness of winning from such a talent level and home field disadvantage.

That’s not to say that there are no benefits. More fans would get to see their team in the playoffs, and even if the math gives them a 1% chance at hoisting a trophy, it doesn’t feel that way in the moment. Every playoff game feels meaningful, regardless of whether one of the teams is overmatched in the tournament as a whole.

Baseball is a regional game, and the new model would make for more regions in the playoffs. It would be brief interest, to be sure; due to the logistical difficulty of squeezing these games in without cutting back on regular season games, they would likely be played on consecutive weekdays, with many of the games happening during working hours.

But all the same, it would probably add to the total amount of excitement around October. In 2019, the Diamondbacks and Mets would have qualified in the NL, and the Indians and Red Sox in the AL. It might offend my sensibilities that the Indians and Red Sox are openly sacrificing wins to enrich their owners, but the Diamondbacks are fun, and fans in Arizona would welcome a chance to watch their team in the postseason.

In 2018, the Mariners and Rays would have made the AL field. Seattle fans have been waiting a generation for a playoff game, and this system would provide it. In the NL, the 88-win Cardinals and one of the 82-win Pirates, Diamondbacks, or Nationals would make the playoffs (there’s no tiebreaker system written down yet).

Is the added regional excitement worth the negative economic incentives around competing? I think not; teams are already doing things like trading Mookie Betts away from a team that would have been a Wild Card favorite in the current format. Relax the entry criteria for the playoffs while making winning the division less valuable, and you’d likely see more of those types of trades.

You’d see a lot more offseasons like this year’s NL Central; the Cubs, Brewers, and Cardinals all went sideways. In the new setup, why not go sideways? If you can’t slug it out with the Dodgers for the best record in the league (and let’s be real, you can’t), you might as well pocket your savings, trade for top Red Sox prospect Financial Flexibility, and see if you can sneak into the playoffs with your current squad.

Maybe you’d see more offseasons like the White Sox or Reds had, teams looking to break into the picture. But I imagine you wouldn’t see all that many; owners are mathematically motivated, and spending to improve your team to a level where you’re 1% likely to win the World Series doesn’t sound very exciting unless there are huge monetary incentives to make the playoffs. Maybe there are — we don’t know all the details of the proposal yet. But most likely, this would just be another way for teams to rationalize not trying to get better.

I’m down on the system as a whole, as you can certainly see. I like the idea that more fans would get a chance to experience the playoffs. I like the idea that there would be more baseball. But I worry that the effect on competition would be too chilling, and given the current state of the game, I don’t think it’s an idle fear. Good-but-not-great teams are already endangered, as Boston and Cleveland have shown us in recent years. Why further disincentivize getting better when the league is already doing it quite efficiently on its own?