Last week, I began a series of pieces about team win-loss totals as estimated by BaseRuns, first by taking a broad look at the methodology and its limitations, then by zooming in on the offenses that deviate most notably from their BaseRuns assessment in the run scoring department. Let’s wrap up with a look at the defenses that sit furthest from their runs allowed approximation.
In the offense edition, I used a game show format to evaluate whether the perspective offered by BaseRuns has a point, or if there’s something its methodology is overlooking. We’ll keep that framework going for the defenses as well. Here’s a reminder of how it works:
To determine whether or not BaseRuns knows what it’s talking about with respect to each team, imagine yourself sitting in the audience on a game show set. The person on your left is dressed as Little Bo Peep, while the person on your right has gone to great lengths to look like Beetlejuice. That or Michael Keaton is really hard up for money. On stage there are a series of doors, each labeled with a team name. Behind each door is a flashing neon sign that reads either “Skill Issue!” or “Built Different!” Both can be either complimentary or derogatory depending on whether BaseRuns is more or less optimistic about a team relative to its actual record. For teams that BaseRuns suggests are better than the numbers indicate, the skill issue identified is a good thing — a latent ability not yet apparent in the on-field results. But if BaseRuns thinks a team is worse than the numbers currently imply, then skill issue is used more colloquially to suggest a lack thereof. The teams that are built different buck the norms laid out by BaseRuns and find a way that BaseRuns doesn’t consider to either excel or struggle.
If we start with the teams BaseRuns has beef with, the White Sox are up first. That’s right, the White Sox were minding their own business, loving life as Not The Worst Team in baseball, when BaseRuns decided to swoop in and offer some notes on their run prevention. Entering Wednesday’s games (as will be the case with all stats cited moving forward), the White Sox have averaged 4.39 runs allowed per game, while BaseRuns contends that number should be more like 4.68.
The primary issue is the volume of baserunners allowed by the pitching staff. And as BaseRuns sees it, once those runners reach base, their odds of scoring are pretty high. Sure, the White Sox rank seventh in groundball double plays, which feels like a positive point in terms of erasing baserunners rather than allowing them to score. However, they rank fifth in batters faced with a runner on first and less than two outs, meaning they get more opportunities to turn double plays. Further, the pitching staff isn’t exactly primed to exploit this wealth of opportunities, as they rank 23rd in groundball rate. And though the infield defense has been mostly fine, with Andrew Vaughn now part of the Brewers organization, the corner positions are left to a patchwork combination of Miguel Vargas, Josh Rojas, and Ryan Noda, who have all been shaky in the field this season. Given their lack of groundball pitchers and premium defense, it’s possible to take an even more skeptical view of the team’s ability to sustain such a high volume of double plays.
One might note that the White Sox have allowed the 11th-fewest home runs, which limits a surefire method of run-scoring. And yet, because of all the baserunners allowed, multi-run dingers make up a much larger chunk of their total home runs allowed relative to other teams.
But perhaps the White Sox make up for all of that by being really good at the thing BaseRuns is known to overlook: preventing runners from taking an extra base on balls in play. Alas, no. Luis Robert Jr. was the team’s strongest performer in this category before hitting the IL with a hamstring strain. That said, their biggest liabilities have been Joshua Palacios and Brooks Baldwin, both of whom have been sent down to Triple-A. But Andrew Benintendi, Austin Slater, and Michael A. Taylor all own a pattern of misplays and weak throws that suggest it’s worth the risk of running on them.
Here’s Benintendi putting his whole body into a throw home that bounces twice before ricocheting off the hitter’s discarded bat on the infield grass:
On this play, Benintendi makes a nice bare hand play as the ball hits off the base of the wall and attempts to throw out Justyn-Henry Malloy at second. Malloy has the play in front of him and picks up speed as he sees Benintendi field the ball, clearly assuming a close play. But the throw sails wide and leaves Lenyn Sosa unable to even attempt a tag:
Here, Slater has a chance to throw out George Springer as he attempts to go first-to-third on a single by Ernie Clement. The throw is a laser that shoots over the outstretched glove of Rojas and stuns the third base camera well instead:
And here, Taylor whiffs on an attempt to cut off a ball as it skitters toward the warning track, which allows Max Schuemann to stretch a double into a triple:
Flinging open the door labeled “White Sox” definitely reveals a skill issue, and though the blinking sign is already lit up like the Fourth of July, it doesn’t hurt to add some fireworks to really drive the point home.
The Phillies are the next contestant to take the stage. Philadelphia allows 4.00 runs per game on average, but BaseRuns believes the club should be allowing closer to 4.25. For the Phillies, BaseRuns isn’t just concerned with the number of hitters reaching base, but also how they reach. Since Philadelphia’s pitchers boast the sixth-lowest walk rate, a larger share of their baserunners reach on hits, and balls in play provide a better opportunity for existing runners on base to advance when compared to a walk or hit by pitch. Drilling down further reveals that it’s not just that hitters reach base on batted balls; the type of batted ball makes a difference too. After posting the second-highest groundball rate in 2024, the Phillies are middle-of-the-pack this season, minimizing the opportunity for groundball double plays, which helps explain why only two teams have turned fewer double plays than they have. Given that this year’s squad returned most of last season’s pitching staff, it’s reasonable to expect the groundball rate to bounce back and for an infield that’s played competent defense to amass a few more double plays.
And if keeping balls on the ground means fewer balls hit in the air, all the better. Outfield defense is a weak point for the Phillies in general, but particularly when it comes to preventing runners from taking extra bases. (Here’s where I have to hope that Jess Castellanos only name searches her husband on social media, because if she has a Google alert set up, this series of videos probably won’t go over well.)
First, we have Nick Castellanos turning either an out or a single into a double:
Here, Castellanos calls off Bryson Stott, then fails to make the catch himself, and when the ball gets past him, Adam Frazier is free to cruise into second:
In this one, Reese McGuire uses his 26th-percentile sprint speed to score from first on a single:
But it’s not all on Castellanos; Max Kepler hasn’t exactly been scaring runners back to their bases either. On this play, Lars Nootbaar goes first-to-third on a single, and the throw from Kepler allows Masyn Winn to go to second:
A Casey Schmitt single scores two after Kepler’s throw all but dies before reaching home plate:
BaseRuns has identified a skill issue — that the Phillies allow too many baserunners on too many balls in play to not allow more runs. And given the state of the outfield defense, the outlook could be even worse. But if there is a ray of hope emanating from the neon sign declaring the aforementioned skill issue, it’s the potential for some positive groundball regression leading to fewer fly balls for the outfielders and more double plays for the infielders.
Now it’s time for the Braves to come on down so we can figure out why BaseRuns estimates their runs allowed per game at 4.18, when they’ve actually been allowing 3.94. This team limits traffic on the basepaths fairly well, but like the Phillies, hitters are disproportionately getting on via hits, thanks to a super low walk rate. And to make matters worse, a lot of those hits are going for extra bases. While the Braves rank seventh in the majors in batting average allowed at .234, they rank 13th in slugging percentage at .389. Meaning that the runners who do reach base are more likely to benefit from a teammate slugging them in. Or they should be. It does seem that the Braves have benefitted from some fortuitous sequencing. As further evidence, they own the highest ratio of solo home runs to total home runs allowed. Such a feat would be justified if they also had the lowest on-base percentage against to match, but theirs is only the 11th-best mark.
Where the Braves may be earning some of their better-than-estimated RA9 is in the outfield. They rate slightly above average by Fielding Run Value when it comes to preventing runners from taking extra bases, with Eli White and Michael Harris II showing out particularly well in this category. And though Ronald Acuña Jr. has posted a negative FRV overall in his injury-shortened season thus far, his 99th-percentile arm strength makes him a positive contributor in heading off runners looking to advance. The outfielders who have held the Braves back in this arena are Jarred Kelenic, who now resides at Triple-A, and Alex Verdugo, who was DFA’d on Wednesday to make room on the roster for Jurickson Profar, who was roughly average on this front in 2024.
You can see Verdugo’s off-kilter outfield presence in plays like this one, where Eric Wagaman sneaks a grounder through the left side, hesitates rounding first, but still makes it to second after Verdugo cuts the ball off, rather than letting Harris field it and make the throw:
Here’s another one where the runner hesitates but still advances, and the trail runner takes an extra base on the throw home:
With Acuña and Profar back, what was already a strength for Atlanta should become even stronger. So while the sign on display behind the door marked Braves does read “Skill Issue!”, there is a “Built Different!” asterisk that mutes the impact of all the extra base hits served up by the pitchers.
Now for the teams that BaseRuns actually likes. The Red Sox have allowed 4.55 runs per game, but BaseRuns estimates that number should be closer to 4.15 because unlike Atlanta, Boston’s opponents reach base more frequently by way of walks and singles rather than extra base hits (they rank 22nd in OBP allowed, but just ninth in slugging percentage). Furthermore, their pitchers get groundballs at a steady clip, ranking sixth in groundball rate, leading to a sixth-place ranking in groundball double plays turned as well. That ranking could be even higher, given that the Red Sox have faced the third-most batters with a runner on first and less than two outs, but an inexperienced infield defense that has been influx much of the season may have cost them a few double plays. The outfield defense, on the other hand, has excelled at limiting runners looking to snag an extra base.
There aren’t a lot of flashy highlights for this type of defense because it frequently amounts to a runner deciding to hold rather than test the outfielder, but here’s Ceddanne Rafaela nailing a runner attempting to grab an extra base on a single from Nathan Lukes:
And here’s Rob Refsnyder unleashing a throw from right field to nab Heston Kjerstad as he tries for third on a Jorge Mateo single:
As this game show’s version of Vanna White opens the door marked “Red Sox,” it becomes clear that there is an issue of skills going unrewarded as Boston repeatedly suffers death by a thousand singles.
The next door on the stage belongs to the Twins, who allow 4.38 runs per game on average, compared to their BaseRuns estimate of 4.19. Minnesota’s on-base against is middle-of-the-pack, and BaseRuns acknowledges that they tend to let those runners score at an above-average rate, in part because they rank dead last in groundball double plays. And it’s not because they’re giving up an untoward number of extra base hits; it’s more that their pitching staff is 27th in groundball rate and their infield defense takes a step back when Willi Castro, Brooks Lee, and Edouard Julien need to cover a slew of innings at second and third. But what BaseRuns can’t square is the high proportion of multi-run homers, particularly three-baggers, relative to Minnesota’s fairly average number of baserunners allowed. Of the Twins’ 90 home runs allowed, 16% have been of the three-run variety, which is tied for the highest ratio among all teams. That can be chalked up to an atypical clustering of baserunners for Twins’ opponents.
But while BaseRuns can account for Minnesota’s infield failing to turn double plays, as we’ve discussed, it can’t account for certain issues with the outfield defense. Only one team (the Cardinals) has been worse than the Twins at stalling runners as they pursue an extra bag.
Harrison Bader, though a strong defender overall, has a lot of throws that look like this:
Here, Trevor Larnach fails to make a competitive throw to stop a catcher from scoring from second on a single:
Larnach also frequently sets himself up to fail on the throw by flubbing his initial attempt to field the ball:
And speaking of flubbed fielding, Byron Buxton often gets dinged for letting runners advance because he is the first fielder to touch the ball after his teammate endeavored and failed to make a diving catch.
See here:
And here:
And here:
In watching those clips, I also ran across several instances where the outfielder had no chance of getting an out because the runner had a huge lead before the ball was even put in play. And sure enough, Minnesota’s pitching staff allows larger leads for baserunners on average (3.9 feet) than all but one other team in the majors (the Marlins at 4.0 feet).
So while the Twins have had some unfortunate sequencing lead to a wild number of three-run homers, opening the door on stage actually leads to an outdoor drone show where the flying glittery lights spell out “Built Different!” as “When Doves Cry” plays in the background. Because the sad reality is this team defies the optimism bestowed upon them by BaseRuns by letting hitters parade around the base paths all but unimpeded.
Now the final contestant takes the stage. The Colorado Rockies allow an average of 6.14 runs per game, but BaseRuns believes it shouldn’t be quite so bad, instead pegging them for 5.79 runs per game. BaseRuns can see that the Rockies have a high on-base against, and that once hitters reach base, their probability of scoring is also high. Just not quite as high as what’s happened in reality. For one thing, the Rockies have turned the third-most double plays, despite having only the 11th-most opportunities to do so. And they actually haven’t allowed the most home runs of any team in baseball, though no one would be at fault for assuming so. No, they’re actually tied for third on that leaderboard. So you can kind of start to see why BaseRuns doesn’t think things are quite as bad as they seem.
By this point in the article, you’ve probably picked up on the general rhythm and pacing, so you know that this is where I tell you that the Rockies are very bad at limiting baserunners as they try to advance and that’s what BaseRuns is missing. Well, joke’s on you, because the Rockies are actually pretty okay at keeping runners in check. Mickey Moniak has some room to improve, but overall the team is a net positive on this front. It’s fair to be skeptical that they can keep turning double plays at quite such an efficient clip when the pitching staff ranks seventh in groundball rate, but Michael Toglia aside, the infield defense has been solid even without Ezequiel Tovar. As easy as it is to believe that the Rockies really are this bad, BaseRuns correctly identifies Colorado’s skill issue: They do have some skills, and it’s an issue that those skills aren’t reflected in their outcomes.
The BaseRuns Game Show will now go on indefinite hiatus. Thanks for tuning in!
Content Source: blogs.fangraphs.com