Layoffs Haven’t Hindered Playoff Teams Historically

On Saturday, three of the four home playoff teams lost the opener of their respective Division Series. The losses ranged from 3-2 dramas to 11-2 laughers. Sunday, the American League teams played their second games, and the home teams went 0-2. Now that we’ve seen six games and the home teams are 1-5, it’s time to ask the obvious question: Is this format irrevocably broken?

Okay, fine, that’s not really a fair question. But there’s been a lot of hue and cry about the playoff system recently, headlined by an article by the estimable Ken Rosenthal that came out this morning in The Athletic, and as the resident “I don’t see what all the fuss is about” guy at FanGraphs, I don’t see what all the fuss is about. What better time to dive into the numbers and see if we can find some interesting facts on either side of this debate.

The biggest gripe, as far as I can tell, is that the layoff between the end of the regular season and the start of the Division Series unfairly disadvantages teams that secured a bye. Their opponents get to play baseball, while they’re forced to sit on their butts. It’s a daily sport, goes the argument; disrupting that rhythm leads to a disadvantage even if extra rest sounds like a carrot rather than a stick.

The current postseason hasn’t been in use long enough to say much of anything about it – a 1-5 stretch for teams with a small edge in the playoffs is hardly noteworthy, and we can’t exactly lean on a hundred years of postseason history to help eliminate the noise. The current playoff format, with 12 teams and two first-round byes in each league, is only two years old. We’re necessarily going to be dealing with small samples here. But let’s start by folding those together with this year’s data, because it will bulk up our sample size considerably.

Last year’s clash of bye teams against Wild Card-round winners was a dead heat. The games were split 8-8; the series were split 2-2. If you zoom in on the first two games of each series, the teams with the bye went 5-3. Zoom in even further, to the first game only, and they went 3-1.

You can go deeper than that. Dan Szymborski culled the historical database for every matchup in playoff history where one team had a layoff of four or more days while their opponent had a layoff of two or fewer days. That counts the last two years of the playoffs, but also games from the two-Wild-Card era, where the top overall seed faced the winner of a winner-take-all game after a brief layoff, as well as the occasional playoff game from earlier eras.

There have been 35 of these games in baseball history. The team with more rest has gone 24-11 in them. Dan also predicted the winner of each of these games based on the team’s seasonal record. From each team’s record, you’d expect the rested teams to go 19-16; they’ve been slightly better in aggregate, which makes sense given the pool we’re drawing from. Here’s a list of all of those games:

Some of that might come down to better pitching matchups; the team with more rest should be able to set their rotation favorably. But that’s kind of the point of the extra time off; sure, in past years it might have been an accident of scheduling, but the league is now using it to give teams an advantage. Getting to deploy your best starting pitcher while your opponent uses a mid-rotation arm is one manifestation of that.

There’s just not much evidence, whether short-term or long-term, that a layoff leads to a disadvantage. Even in the past two years, home teams have gone 4-4 in the first game of the Division Series. That’s the period that everyone is most worried about, and it’s still been a dead heat. It’s also simply not enough data to say much of anything; eight games isn’t much of a sample, particularly when all the teams involved are playoff caliber.

Though I don’t see much evidence that a layoff is hurting the best teams, I do sympathize with the impulse to give higher seeds more of an advantage. The expanded playoff field has given more fanbases a taste of the postseason, but there’s also an implicit danger: the more teams you allow into the playoffs, the less sense it makes to expend resources trying to qualify. If each of the 12 playoff teams had the same chances of winning the World Series, the game would suffer. No one would try for 100 wins if winning 88 gave you the same odds, or even roughly equivalent odds, of winning the big prize at the end of the year.

Byes are an important way to provide differentiation between the best teams in baseball and the next tier down. Winning 90 games is less appealing than it once was. In the last two years, six seeds have won 84, 86, 87, and 89 games respectively; two teams made the NL playoffs after winning 84 games this year, in fact. I think it’s important to counter that pull towards the middle by giving the very best teams an advantage.

Historical data suggest that the extra layoff is a meaningful advantage, but there are always more options to incentivize teams to win. John Smoltz suggested something I’m quite fond of: eliminating rest and travel days to compress the time between the Wild Card series and the next round. That would force non-bye teams to either use pitchers on short rest or expand their rotation to include lower-tier starters. It would particularly blunt the advantage that teams like the Phillies, Twins, and Diamondbacks, who have two elite starters, currently hold.

The playoffs have always tilted the equation towards more starts from your best arms and fewer from the back of the rotation, but the padding has gotten bigger in the new playoff format. Wild Card teams are supposed to be disadvantaged by having to play more games in less time, but after tonight’s games, the Phillies and Diamondbacks will have each played four games in the last seven days. I don’t think there’s any evidence that the extra layoff is hurting the teams that receive byes, but the lower seeds are hardly facing an impossible burden from playing extra games. They, too, have far more rest than they’re used to in the regular season, and this effect is even more pronounced this year, thanks to all four Wild Card series winners sweeping. If we’re trying to create a disadvantage for lower seeds, this system isn’t doing that.

Fixing this might be untenable for the league, because it’s set up the way it is largely for TV reasons. As Rosenthal pointed out, cutting out a travel day between the last Wild Card game and the first game of the next round would mean playing afternoon games, something the league’s broadcast partners wouldn’t like. The NLDS also has a non-travel off day this year, just like the ALDS did last year. That sticks out like a sore thumb – but it’s there so that the league can start all four Division Series on the same day and still broadcast multiple games on TV every day. Today would be a travel day for all four series otherwise, and MLB seems to prefer blanket coverage to an equal playing field between the two leagues.

Rosenthal suggested reseeding the playoffs after the first round, and I think that’s a no-brainer. It wouldn’t affect very much at all, in my opinion, but it’s better than the alternative of not reseeding. Granting the top seed in each league an additional marginal advantage at no cost to the broadcast schedule, which seems to be the reason the league has resisted other attempts to give that top seed an edge, is a great idea.

While I don’t believe that the current playoff system is giving top seeds a disadvantage, I do think it’s important to be vigilant about protecting the edges that better teams receive. Competitive balance is never assured in a sport with revenue sharing and no salary floor, and particularly one where the outcome of short playoff series is always heavily random. The better team advances in 80% of seven-game NBA series; Michael Lopez, Greg Matthews, and Ben Baumer found that MLB would need a best-of-75 series to match that rate. If you want the best teams to play in the World Series every year, baseball’s inherent randomness is a huge headwind.

So good on everyone for obsessively searching for any other roadblocks and attempting to remove them. I think the impulse to make sure that the current playoff format treats good teams fairly is commendable. I want the design to give top teams an edge, never mind parity. A system that hurt them would be unthinkable. I just don’t think that layoffs and rest days are serving to blunt that edge.