FanGraphs Weekly Mailbag: September 26, 2026

We’ve made it to the final weekend of the regular season, and while all but two of the 12 playoff teams have been determined, two divisions titles and one Wild Card berth are still up for grabs. Both the Guardians and White Sox have already clinched a spot in the American League bracket, but only one game separates them in the standings. Cleveland, the first-place team, needs to win the division outright because Chicago owns the tiebreaker. The stakes are high; the victor earns the second seed in the league, a first-round bye, and home-field advantage in the Division Series, while the loser has to play the entire best-of-three Wild Card Series on the road.

The club that finishes second will face either the Astros or the Rangers, who both lost Friday night and fell to 79-81. There’s a very real chance that AL West winner will become the first playoff team ever to finish a full-length season with a losing record. Houston holds the tiebreaker. This race is emblematic of two things wrong with the current rules: 1) We should not allow losing teams to make the postseason, and 2) ties should be settled by one-game playoffs, not math. As if to provide further support for my second point, over in the National League, the surging Diamondbacks are making a last-gasp bid to overcome the reeling Phillies for the final Wild Card spot. Riding a six-game winning streak into Saturday, Arizona is just one game behind the Phillies, but crucially, the Snakes would get in if they finish with the same record. The two teams split their six regular-season matchups — head-to-head record is the first tiebreaker — but the Diamondbacks have the better intra-divisional record, which is the second tiebreaker. Goofy! It’s still going to be a fun baseball weekend, and the playoffs are sure to be a thrill, but think of how much more excitement there would be if we had not one, not two, but three Game 163s on Monday. What could have been.

Before we get to this week’s mailbag, I have one quick programming note. We’ll still be doing our weekly mailbag during the postseason, but we might move around the specific day it runs depending on the playoff schedule. As we did last year, our plan is to do a mailbag before every postseason round, beginning with the Division Series. Also, in case you missed David Appelman’s announcement from Thursday, this year you will need a FanGraphs Membership to read our postseason coverage. You can find all the details in David’s post, but considering our mailbags are also exclusive to FanGraphs Members, most of you reading this probably won’t notice the change. However, what you will notice and appreciate is the other major part of David’s announcement: This October, we’re committed to having staff at every World Series game, allowing for additional reported work and greater access to players and team personnel, with more in-person coverage throughout the earlier rounds as well. In recent years, we’ve had in-person World Series coverage only when the games were played in a city where one of our writers lived. Now, we’ll be there no matter what. If you aren’t yet a Member and would like to both keep reading this mailbag and get access to our postseason coverage, you can sign up for a Membership here. It’s the best way to experience the site and support our staff, and it comes with a bunch of other great benefits. Also, if you’d like to ask a question for an upcoming mailbag, send me an email at [email protected].

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Hey FanGraphs,

WAR per inning isn’t directly documented anywhere. You get the feeling though that Mason Miller’s 3.7 WAR this year (so far) in 64 1/3 innings has to be one of the highest single-season rates ever for a pitcher with 40-plus innings pitched. Am I right, and is this maybe the best way to gauge just how historic his season continues to be?

Thanks for the bag!

Baseball Learner

Jon Becker: Hey Baseball Learner! I’ve answered a handful of “I bet this guy is way up there on this list!” mailbag questions, and in most cases, the question-asker is underestimating just how long baseball’s history is, and the player-season in question really isn’t that high on the list. That’s not the case with your question. Through play on Thursday, Miller upped his WAR since you asked your question to 3.8, in 69 innings pitched. That works out to .055 WAR per inning pitched, sixth all time among the 31,064 player-seasons with at least 40 innings. Here’s the top 10:

This list is unsurprisingly dominated by elite reliever seasons, shortened starter seasons (whether due to injury in Jacob deGrom’s case or fewer unearthed games for the four Negro Leagues pitchers), and of course, the best pitching season all time: 1999 Pedro Martínez.

Also high on the list from this season are Jhoan Duran (22nd), Josh Hader (62nd), and Trevor Megill (77th). Among starters, Jacob Misiorowski leads with .038 WAR per inning, good for 126th all time.

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FG,

Why don’t we discuss pitching performance using wOBA more? It’s primarily still ERA or FIP everywhere you look.

Metrics based on linear weights I think would be a very sensible way of looking at how well a pitcher is doing. Doesn’t account for sequencing like ERA (which I personally like, not everyone does), doesn’t ignore doubles and stuff like FIP (again, sounds good to me). If you’re worried about defensive contribution you can line it up against xwOBA to check if it’s being fair. No park adjustment, but maybe you switch to wRC+ when you want that? Maybe wRC+ is even better?

And wouldn’t it be nice to have the same measure for pitchers and hitters so we use the same standards of what’s good or bad?

Am I wrong for being a pitcher wOBA guy? Are there more like me?

Yer Main (wOBA) Guy

Davy Andrews: Main Guy, you are not wrong and you are not alone. I asked around, and unfortunately it sounds like we don’t even calculate pitcher wRC+. However, I look at pitcher wOBA all the time, and I would look at it even more often were it more easily accessible. That’s not to say that it’s necessarily better than the other options. As a proxy for true talent level, I quickly pulled every pitcher’s Statcast-era performance according to a bunch of easily accessible metrics and calculated their correlation to the next year’s ERA.

As you can see, xwOBA is as predictive as xFIP. wOBA’s better than ERA, but not quite as good as FIP. In other words, they’re perfectly reasonable ways to assess a pitcher, but it’s not like they’re so good that we should be out there convincing people to junk their preferred ERA estimators.

As for why they’re not more widespread, you’re probably aware of the reasons. The obvious one is that people have spent their entire lives viewing pitching through the lens of ERA. That’s their primary language, and it’s the reason that all our advanced ERA estimators (and even PitchingBot!) are formatted so you can read them the way you’d read an ERA. We could certainly do that with wOBA and xwOBA too, and maybe that would make people a bit more receptive to them, but you still run into the fact that they’re not all that much better.

Then you have the overkill factor. There are so many ERA estimators out there already. The Onion is out here roasting FanGraphs specifically for making up new junk stats, and even drummers are getting in on the action. Drummers! Each pitcher’s player page already lists ERA, ERA-, xERA, FIP, FIP-, xFIP, xFIP-, SIERA, and botERA. I like pitcher wOBA and xwOBA, and I’m as curious as you are about whether wRC+ might be helpful too. And, of course, I am generally in favor of more information. I am on your side. But I can understand why adding them to the site isn’t a priority.

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Hi!

I have two questions:

1. Do you feel that the rules should be changed to allow players to throw their gloves up in an effort to block a home run from going out? If this rule changed, do you think we’d see players doing it?

2. Suppose there’s a runner on third and you’re an outfielder. You have a sac fly hit to you. Would it be legal to essentially juggle the ball while running into the infield so the runner is unable to tag up, as by the time you actually “catch” the ball you’re by home plate?

Thanks!
Russell

Michael Baumann: You’re so greedy, Russell, sneaking two unrelated questions into the same mailbag email. But we aim to provide value for money here at the FanGraphs factory, so let’s press on.

To your first question: Absolutely not. I know that baseball is a kids’ game and all, but these are adults, and we’re not going to be throwing our toys at a passing baseball like a seven-year-old having a sugar crash. It’s undignified. I won’t have it. You can tell how much I hate this idea because I’m placing Rule no. 1 of improv comedy — “Always say, ‘Yes, and…’” — right in the oubliette.

The only scenario in which I’d support changing the throwing-the-glove rule is one in which a fielder may throw his glove in an attempt to knock down a would-be home run ball — but if he misses and the glove goes into the stands, he may not ask for it back. It’s gone forever. You’ve got to break in a new glove from scratch.

If the fielder misses the ball and the glove lands in the field of play, he can have it back at the end of the game, but he has to play the rest of the game barehanded. If the manager wants to have a left fielder with a full set of equipment, he has to burn a substitution. You had your chance to play with a glove, and you decided you’d rather throw it at a fly ball.

Even if the rule changed, I don’t think anyone would throw his glove at a passing fly ball. For starters, a baseball traveling at 100 miles an hour has a ton of inertia, and even if you did hit it, I don’t know how much a glove would do to stop it without a human arm attached. Even if you did knock it down and keep it in the field of play, you’re now chasing a fugitive baseball in God-knows-what direction without a glove of your own. You might’ve just changed an outside-the-park homer to an inside-the-park homer.

On to question no. 2. My favorite thing to do in these mailbag columns is to cite chapter and verse from the rulebook. For instance, did you know that Rule 3.06 defines the area between the thumb and forefinger of a fielder’s glove as the “crotch?” You learn something new every time you open the rulebook. I thought the crotch was something completely different.

Anyway, Rule 5.09(a): “A batter is out when (1) His fair or foul fly ball (other than a foul tip) is legally caught by a fielder;” would seem to leave the rule open to exploitation along the terms Russell describes. And while the rulebook is littered with comments and hypotheticals to assist the umpires in executing the rules, there is no such addendum to Rule 5.09(a)(1).

Until you get to “Definitions of Terms,” way down on page 148 of the rulebook. I’ll quote again from the Holy Scripture:

“A CATCH is the act of a fielder in getting secure possession in his hand or glove of a ball in flight and firmly holding it; providing he does not use his cap, protector, pocket or any other part of his uniform in getting possession.”

So you’d better be careful what you touch the ball with when you’re juggling it. If it hits your body or the bill of your cap, it’s no longer a catch, the runner on third is going to score, and your manager is going to yell at you until you go deaf in that ear.

And later in that same paragraph, it gets worse:

“A catch also is legal if the ball is finally held by any fielder, even though juggled, or held by another fielder before it touches the ground. Runners may leave their bases the instant the first fielder touches the ball.” (Emphasis mine.)

That means the outfielder can juggle the ball until the cows come home, but if the runner has tagged up after the initial touch, he’s free to leave for the next base regardless of when the catch is completed. I guess you could gamble on the possibility that both the runner and the third base coach don’t know this rule, but the law would not be on your side.

We get rules questions like this pretty frequently, from people who watch a ton of baseball and find what look like loopholes. If you’ve been watching baseball for 20 years, you’ve never seen a clever outfielder try to juggle his way out of a sacrifice fly. That must be incomprehensible — it’s such an obvious gap in the rules, surely someone should try to exploit it!

The thing is, we’ve been playing organized baseball for 150 years now, and in that time a lot of very smart, very cunning people have spent lots of time poring over the rules looking for weaknesses. If you think you’ve found a loophole, odds are that someone — not always John McGraw, Jackie Robinson, or Don Hoak, but it’s usually literally one of those guys — has tried it already.

If the loophole did actually work, Ford Frick or Happy Chandler would come into the office the next morning and scrawl “KNOCK THAT BUSH LEAGUE NONSENSE OFF” in the rulebook, thus ruining the fun of future ballplayers and mailbag letter-writers alike.

This is a pretty common phenomenon in society at large, actually. We have a problem, we make a rule to fix the problem, the rule fixes the problem, we forget the problem ever existed, we get rid of the rule, the problem comes back. Except nowadays it’s with stuff like labor regulations, white-collar crime, and food safety, in addition to the governance of fly balls.

It’s why I’m convinced that there will be a nuclear weapon detonated in anger, somewhere in the world, by the year 2100. As soon as the Cold War is out of living memory, the atomic taboo is going to fade, and some world leader is going to think, “What was the big deal about Hiroshima anyhow?”

In short: Don’t throw your glove, stop fooling around and make the catch as quickly as possible, and someone has already tried your loophole and gotten in trouble for it. Thanks for writing in, Russell. If you ever find yourself on MLB’s rules committee, please let me know so I can move to Cambodia.

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