Through Two Rounds, These Postseason Games Have Been Up in the Air

We’ve come to expect the characteristic intensity of the MLB postseason. The league’s best teams meeting head to head with everything on the line is bound to generate some memorable storylines, and two weeks in, the 2022 playoffs have been no exception. The top four seeds in the NL — the Dodgers, Braves, Cardinals, and Mets — were upset by the Padres and Phillies, leading to heated debate on the merits of a playoff format that remains a crapshoot. The Mariners ended their drought and beat the Blue Jays on the road to earn a playoff game in front of their long-deserving home fans before falling in the ALDS to Yordan Alvarez and, eventually, Jeremy Peña. The Yankees and Guardians traded blows for five games in the only Division Series to go the distance.

What is not a given in the playoffs is that, independent of the stakes of the game, the games themselves will be competitive. With the level of talent on the field, we expect to see some worthy contention, but it is an inevitability of the sport — maybe an inevitability of sports in general — that some games end up as back-and-forth nailbiters and others as, well, something like 8–2 in the fourth inning. The results may be the same, but baseball is, after all, about the fan experience, and it’s a heck of a lot more fun to watch when you don’t know who’s going to win. This postseason, we’ve been lucky to get more of the former than the latter.

To try to quantify the experience of watching these games, we can turn to Win Expectancy. By giving us snapshots of who has the advantage in the game, and by how much, Win Expectancy gives us a pretty good sense of how exciting a game is to watch. A game in which the winning team has an 85% Win Expectancy in the fourth inning, as the Yankees did in Game 5 on Tuesday, is obviously not as exciting as a game with something closer to a 50–50 split. The most exciting games might involve a lot of swings back and forth, but generally speaking, if most of the game is spent with the outcome up in the air, that makes for a pretty good game to watch.

In other words, we can try to distinguish a “good” game to watch from a less exciting one by at what point the eventual winning team took a position of pretty clear control — say, somewhat conservatively, a 75% Win Expectancy. That’s an arbitrary threshold, so let’s take a look at a few examples of what that means.

In Game 1 of the Phillies-Braves NLDS, Philadelphia scored twice in the bottom of the first. Atlanta took one back before the Phillies scored two more in the third, two in the fourth, and one in the fifth, broadening the lead to 7–1. The Phillies lifted their win probability over 75% when they went up 4–1 in the third, hovered around there for about half an inning, and then passed 75% for good after holding Atlanta scoreless in the bottom half. This seems to pass the sniff test. From the point the Phillies expanded their lead to 4–1, the Braves weren’t all that close to winning, until Matt Olson brought them within one with a three-run homer in the ninth — but with just two outs left to tie it. Atlanta’s win probability never rose above 11.4%.

For another example, take another Game 1 from that same day. Hosting the Padres, the Dodgers went up 5–0 in the first four innings, reaching a 95% Win Expectancy. But San Diego battled back, scoring three in the fifth, and when the Padres started to rally in the sixth, they briefly diminished Los Angeles’ win probability to 65.3%. That makes sense: For a moment, the Padres were back in the game, and it’s fair to imagine they might have had about a one-third chance of winning it. This game should get credit for becoming exciting again. But with a rally-killing double play, the Dodgers jumped back over 75% and never looked back.

We can tweak the evaluation one way or another, but this seems to make a pretty good case: the later into the game that the winning team passes 75% for good, the more likely that game is to feature the kind of drama that makes a game great to watch.

A few quick notes: first, because of the stakes of the games in the playoffs, the fan experience is pretty heightened. While in the regular season, a game in which a team pulls out to a 4–1 lead in the third and never loses that lead is, in all likelihood, not that exciting a game, we probably feel a bit less comfy with that lead in a postseason game. The threshold for a game being “boring” is much higher. But this is probably more about the impact a loss would have and less about the chances of it happening being any different. In any case, arbitrary as it may be, this 75% threshold can help us quantify the control the eventual winner has over the game.

Also, note that I’ve specified the winning team a few times. If the team that first passes 75% ultimately loses the game, that indicates a pretty exciting game. Take a third Division Series Game 1: the Mariners jumped ahead to a 4–0 lead and an 85.6% win probability in the second inning. That mark was at 91.4% when the final pitch was thrown to Alvarez, who hit it for a walk-off home run, representing the most dramatic shift in win probability in a single play in playoff history. This, it goes without saying, should get credit for being a very exciting game.

Through the Division Series, the 12 playoff teams played 25 games. In 17 of those games, the winning team passed the 75% threshold for good in the sixth inning or later. In over half, the threshold was passed in the seventh inning or later. And in seven, that threshold wasn’t eclipsed until the ninth inning or later, including three extra-inning games that ended in the 10th, 15th, and 18th. In other words, in only eight games this postseason — 32% — was Win Expectancy at least 75% confident of the eventual winner for as much as the last four innings.

This represents a marked swing from last season’s playoffs, when 16 of 37 games, 43%, were “decided” — i.e. the winner was favored by odds of 75% or greater — before the sixth inning.

Another metric we can use to evaluate the in-game intensity, independent of the stakes of the game, is Leverage Index (LI), which effectively measures suspense by identifying opportunities for swings in Win Expectancy. A plate appearance that stands to have a large impact on the outcome of the game will have a high LI, and a plate appearance with little potential for impact will score low, with 1.00 representing the average. These methods for evaluating the competitiveness of a game are related; when one team has a chance of winning greater than 75%, LI scores will be lower than when the odds are closer to even. We can use Championship Leverage Index to identify swings in World Series odds, but for the purposes of looking at the intensity of the games themselves outside of the playoff context, regular old LI will do the trick.

Through the end of the Division Series round, a not-close ALDS Game 5 notwithstanding, this year’s playoffs have an average LI of 1.04, which would rank as the highest for a full postseason in nearly a decade since 2014 (1.15), and significantly higher than last year’s 0.94. Including only games through the DS for previous seasons, this year’s mark was the highest since 2016 (1.14). This indicates that the overall suspense of the average plate appearance over all games this postseason is elevated from past years.

These averages include all of the lower-leverage games in addition to the ones with high aLIs. But another way to look at the leverage is how many of the games themselves have high aLI scores, indicating that they maintained a high level of intensity throughout most of the game. Through the Division Series this postseason, there were 50 team pitching games, and 14 of those posted aLIs higher than 1.25, including seven with scores over 1.50. This measure, too, places 2022 among the more intense postseasons in recent memory.

So what does this all mean? Well, there’s little to suggest it’s anything but random. It’s not necessarily that teams this postseason are more evenly matched or that gameplay has changed in some way to intensify the on-field product. It doesn’t necessarily predict that that the NLCS or ALCS or World Series will feature more close games than usual. It’s possible that an elite pitching matchup might give you a higher chance of a tight game, but for the most part, whether you get a nailbiter or a blowout in any given game is a roll of the dice.

What it does mean is that so far this October, we’ve gotten an intense, competitive playoff atmosphere at a level we haven’t seen in years, and it’s worth appreciating that fact for what it is. This in-game intensity is what creates the environment for some of our historic playoff moments: 15th-inning walk-off home runs, clutch shutdown saves, games down to the final strike. May we be so lucky to see more in rounds to come.