We've officially reached September. And, of course, no one in a front office would ever think about saying this out loud, but there are starting to be some discussions about the eventual playoff roster. If we get there. Of course. Gotta clinch first (and so far, no one has!) But ... if we got there ... who would be on our list of 25?
Playoff baseball is a little different than regular season baseball. Oh, there's still three strikes and you're out, but everyone knows that the roster works a little differently in October than it does in August. There are more days off. You don't need five starters. Salvador Perez can play in every single game. But, most fans don't really give a second thought to who should be on the roster. Just take the best 25 (healthy) players or perhaps just use the 25 guys who were on the roster for the regular season. If you usually went with a seven-man bullpen, go with a seven-man bullpen in the playoffs. Make sure you bring your utility infielder, because ... you need to bring your utility infielder.
But let's stop for a moment. Does it really make sense to build a roster for the playoffs the same way that you built it for the regular season? Sure, most of the roster writes itself. If the Pirates make it, Andrew McCutchen will be on their roster. If the Blue Jays make it, David Price will be there. I heard the Royals might have a bullpen guy or two or three that they like. But what to do with spots Nos. 22-25 on the roster? Is there a better way to allocate them than "just bring the guys who got you there?"
Warning! Gory Mathematical Details Ahead!
Let's establish a few things. We know that teams usually only have three or four guys who actually make postseason starts for them, just because of the schedule. Often they'll bring the guy who actually was the fifth starter along for the ride in the playoffs and designate him as the official "long man," but teams certainly have the luxury of at least that roster spot to play with, either to bring a different player or just know that they have another arm in the bullpen.
But we also know that teams change their roster management strategy in other ways during the course of a playoff series. I looked at how playoff teams from 2010-2014 actually used players and then compared them to how players were used from Aug. 1-15 of those seasons. There's nothing sacred about those dates, other than I just wanted to get a two-week period during the regular season (before the expanded September rosters) for comparison.
* Teams don't rotate the squad as much. Among the 40 playoff teams in the sample (I excluded the Wild Card Game losers), six of them started the same nine guys in all of their playoff games and two-thirds of all teams (note: for National League teams, I counted "starting pitcher" as the same guy, even though the person occupying that particular slot was different in each game) used only nine, 10, or 11 players in their starting lineups during their playoff run. During the regular season, there was only one team in the five years I studied that used as few as 11 players in their starting lineup during that two-week period, and there was a big cluster around 14 and 15 players.
* I looked at each team's nine most-used players in the starting lineup during their playoff run. A guy who wasn't one of those nine regulars appeared on the team's lineup card an average of once every other game. In August, there were 1.45 of these bench guys on the lineup card per game.
* In AL-rules playoff games, there were 1.13 pinch hitters used per game (by both teams). In the NL, where pinch-hitting for the pitcher is a thing, there were 3.44 pinch hitters per game (again, both teams). There might have been more "pinch hitters" used in NL games in the form of double-switches, but I wasn't able to count them. During the regular season, the AL games had 0.81 pinch hitters while the NL had 3.25 pinch hitters. Teams might not rotate players in and out of the starting lineup, but during the playoffs, managers are more likely to use all of their bench within a game.
* In AL-rules playoff games, there were 0.64 pinch runners used (both teams); in NL games there were 0.46. During the regular season, those numbers were 0.40 and 0.19.
* The average playoff starter faced 23.7 hitters and recorded 16.9 outs in the playoffs. During the first two weeks of August, he faced 25.6 hitters and recorded 18.1 outs, although there's a bit more variability in those numbers in the playoffs, meaning that you're more likely to see a three innings-or-fewer start (4.0 percent in the regular season vs. 9.0 percent in the playoffs) and an eight innings-or-more start (3.3 percent during the regular season vs. 4.2 during the playoffs) in the playoffs than during the regular season.
* Reliever roles change a bit, too. Relievers who enter in or after the sixth inning in a playoff game face an average of 3.7 batters and get 2.7 outs. In an average playoff game, teams use 3.49 relievers. During the regular season, relievers face an average of 4.1 batters, get 2.9 outs, and teams use 2.84 relievers.
* A lot of the above has to do with managers being more willing to play matchups during playoff games. During the regular season, 29.6 percent of relief appearances lasted two outs or fewer outs and 44.2 percent lasted three batters or fewer. In the postseason, 40.7 appearances were less than an inning and 52.9 percent of relievers faced three or fewer hitters.
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From this data, we can make a couple of recommendations on which types of players make the most sense to pack:
Utility infielder/outfielders: Many teams pick their utility guy based on the fact that he is the best overall player who is willing to be a backup and can play multiple positions competently. He's probably not a good player (or else he'd be starting), but he might be a reasonable hitter with just enough glove to not be a total embarrassment at short or he might be a defensive whiz who can't hit. The reason that you pick the best overall player is that one to two times per week during the regular season, he'll have to fill in for one of the infielders because they get hurt or need a day off. But in the playoffs, giving a guy a day off isn't an issue. Someone might still get hurt, but if the utility guy plays, it's much more likely that he would do so as a pinch hitter. So, if a team has a couple of backup outfielders, one a good hitter but with limited defensive chops and the other a more rounded player, it might make sense to take the better hitter, even if his Madden OVR rating might be a few ticks lower than the other guy. (We'll see in a moment, you can make the same case for a guy who is an all-glove, no-hit specialist as well!)
Matchup relievers: A guy with extreme platoon splits is hard to include on a roster during the regular season, if only for the fact that he's only good against one side or the other and likely has a hard time pitching to more than one or two batters. During the regular season, that's a luxury, because the bullpen has to be able to handle a certain amount of work. But in the playoffs, it can be a good idea to pack an extra one of these. For example, the Twins lefty Aaron Thompson has a career line of .320/.390/.456 when facing righties, but .250/.295/.375 when facing lefties. He might be a good candidate ... if the Twins make it.
Tandem starters: In the playoffs, you're more likely to see a starter pulled in the third inning because every game matters so much. Sometimes a manager has to be really quick with the hook. But here's an idea. One problem that some starters have is that they would be great if the assignment was to throw 50 pitches, but not 100. If you have two of those guys, why not simply pair them up and have them be your Game 4 two-headed starter? The Rays aren't likely to make the playoffs, but they've had some success with this sort of model this season.
Designated pinch runners: It's become something of an unofficial position on the playoff roster. A guy who's really, really fast, but not very good at the rest of baseball. He probably won't be needed the rest of the series to do anything, so why not have him available to run? The Dodgers were reported to have opened up an audition camp for these speedsters and depending what you believe, traded for Jose Peraza from the Braves mostly because he might be able to fill this role.
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But let's say that as a team is putting together its list of 25, and it has one last spot left (and has fulfilled all the basic needs). And on the table are ...
1. A really fast guy
2. A lefty specialist reliever
3. A guy who is a defensive whiz, but can't hit
4. A guy who can't field, but my can he take a nice big swing
5. A reasonable hitter who balances out the bench in terms of handedness
Some of this, of course, will depend on the rest of the roster. If the lefty specialist would be the fifth lefty in the 'pen, that's overkill. But which one would provide the most value? At least, on average.
It turns out that a pinch runner can be useful when the situation that calls for him comes up, but it requires a very specific set of circumstances (someone gets on first, whom you don't mind losing from the game, who is slow, and there are no runners ahead of him) to happen. But Dave Roberts notwithstanding, a good pinch runner isn't as important as you might think, mostly because it's rare that he's used, and even when he is, he's not a guarantee to steal a base. In 2012, Sam Miller calculated how much Billy Hamilton might be worth to the Reds used as a pinch runner down the stretch and came up with a one-month total of perhaps 0.1 wins added to the team. Over the course of six months, he might be worth a little more than half a win or so, and that's Billy Hamilton.
A good defender might be used as a defensive replacement, perhaps in the eighth and ninth inning of a game. The value that even a good defender brings to a team on a per-inning basis is fairly negligible. Figure that an amazing defender is generally one who is worth about 20 runs more than the league average at his position. Let's say that he replaces someone who is 10 runs below average over a full season (1,350 innings, or 150 nine-inning games). That upgrade worth about 0.022 runs per inning, and generally can be used every game. If a manager could get that upgrade for two innings across 150 games of a season, his team would be 6.6 runs better. During a short series, our defensive whiz might never have a ball hit to him (or might field a ball that any competent major leaguer with a glove could have handled). He might also end up winning Game 7 with a web gem. But on average, he's not a bad guy to bring along.
If you don't happen to have an all-world glove guy, you might want to bring an extra hitter, perhaps a guy who can get you a platoon advantage, either on the pitching or the hitting side of the ledger. We know that a manager would have plenty of chances to use this advantage because new hitters seem to come up every few minutes. And we know that because managers like to go to their benches and bullpens more frequently, it's probably an issue that might come up a time or two, even if this guy is the last bat on the bench. In fact, just knowing that he's there and could come off the bench might make the opposing manager think twice about bringing in a lefty (or a righty). After all, in 2015, the platoon advantage has been worth about 20 points of OBP. A pitcher might be able to pitch to two or three consecutive same-handed batters (although as we've seen, the manager would be much more likely to pinch-hit and that platoon advantage might quickly become a platoon nightmare and he might have to pitch to that batter.)
A batter would probably only get one shot, but he's more immune to having a reliever thrown against him (his manager can simply double-pinch-hit for him). Twenty points of on-base percentage is worth an extra two percent chance of getting a hit or a walk instead of an out. Changing an out into even a single or a walk is worth about three-quarters of a run, so a two-percent chance of doing that is worth about 0.015 runs. That might not sound like much, but over the course of 600 plate appearances (a full season of regular playing time), that's nine runs. If a manager could always count on being able to have the platoon advantage even one extra time during a game, using the standard conversion factor that 10 runs equals one win, his team would be almost one win better. That's a lot of value.
We haven't yet considered the possibility of the classic monster bat with absolutely no glove, though. It's possible that such a hitter exists who would be one win better with his bat than some bench guy even when he doesn't have the platoon advantage, but who wasn't worthy of a roster spot in the regular season because his defense was just that awful (but who might be viable in the postseason in a strictly pinch-hitting role). Not to pick on the Twins, but a guy like Oswaldo Arcia comes to mind. But guys who fit that role are often either already on the team and DHing or teams are desperately trying to hide them in left field.
When you look at the numbers, October baseball really is different. And around the edges, you begin to see that certain types of players who might not make sense in the regular season might make sense in the postseason. It also looks like there is room for a little improvement. Teams appear to be obsessed with having a designated pinch runner, when they might get a little more bang out of a good defensive replacement. But first, they need to make sure they have several options for maintaining a good platoon advantage. Hopefully, they already have a good selection of both right- and left-handed bats on the bench (and in the bullpen), so this might not be an area of need, but they do need to be ready. So, if you're lucky enough to cheer for a team that's head for October (or are a bandwagon hopper) and you see a surprise name on their playoff roster, it might not actually be much of a surprise when you think about it.
