How Productive is a Tyler O’Neill — Alex Verdugo Swap, Actually?

The Red Sox played musical chairs with their outfield this past week. Was it worth it?

Kees van Hemmen
9 min readDec 10, 2023

On Friday evening the Red Sox acquired Cardinals’ outfielder and right-handed hitter Tyler O’Neill in exchange for AAA reliever Nick Robertson and an organizational depth piece in RHP Victor Santos. Earlier in the week, the Red Sox had sent outfielder and left-handed hitter Alex Verdugo to the Yankees in exchange for three arms: Richard Fitts, Greg Weissert and Nicholas Judice.

Fitts is the center piece of the latter trade. He projects as a back end starter or a high leverage reliever in the majors, and he was stellar last season in AA with two potential plus pitches. If he adds a third he could factor into the 2025 rotation, with this Fangraphs article saying he could be a top 100 prospect should that come to pass. Weissert can get major league outs and has options. Judice is a wild card with a huge, projectable frame.

On balance, I like these two trades. I think the arm swap in question here is a win: I liked Robertson, but it’s difficult to argue that he’s a better prospect than Fitts, and Robertson had to be carried on the 40 man whereas Fitts does not. Santos and Judice aren’t so far apart in value, and then the Sox also came away with a controllable major league contributor for next year in Weissert. And that’s without even looking at the give-and-take of the outfield swap in question.

When comparing O’Neill and Verdugo, there are a lot of ways to look at it. There’s the surface level look: both have slightly above league average career output at the plate (111 career wRC+ for O’Neill to Verdugo’s 107 career wRC+), both have reputations as good defenders (O’Neill has two golden gloves in left, Verdugo was a finalist for one in right last season).

The surface level look fails to tell the whole story, though. Let me explain.

Starting with the more trivial and moving towards the more substantive, it’s noteworthy that O’Neill is consistently one of the fastest players in the Majors. Last season was the first in his career where he wasn’t one of the 16 fastest players in terms of sprint speed according to baseball savant. You could attribute that to the slew of injuries that have affected him since 2021 (and I’ll get to that later), but even still, last season he remained a full foot per second faster than Verdugo’s career best sprint speed (28.5 to Verdugo’s 27.5). This bears out on the basepaths: Verdugo’s been worth about half a run on the basepaths over his career according to Fangraph’s BsR, whereas O’Neill has been worth almost 9. So this is an upgrade in a base running sense.

Moving onto defense: though Verdugo may have a comparable reputation in the field, he simply is not as good a fielder. His cumulative career Outs Above Average is -4. Granted, last season he was at +1 in Fenway’s colossal right field, and in his prior 3 seasons he had probably been unfairly docked by the advanced metrics because he played in front of the Green Monster, but nonetheless it’s difficult to substantiate the idea that he’s a better fielder than O’Neill. O’Neill has +11 OAA on his career, and he’s never had a season where the metric had him as a below average fielder. Fangraphs’ UZR and DRS metrics also both prefer O’Neill, though the margin is much smaller. Verdugo grades out very well in arm strength as per baseball savant, but O’Neill’s just behind him. On balance, the evidence here is that this is a defensive upgrade.

Things are probably closest at the plate. As mentioned before, their career output at the plate is comparable. That said, they’ve gotten to similar spots in very different ways. Whereas Verdugo’s been the picture of consistency (albeit unspectacular consistency) with wOBA values of .334, .319, and .322 over the last three years, O’Neill has been all over the place. In 2019, O’Neill was legitimately one of the best players in baseball with a .387 wOBA. Since then? He’s been very average, with values of .307 and .313 in 2022 and 2023 respectively.

There are two ways you could read these numbers. There’s the first possibility, which is that the 2021 season was an anomaly, and O’Neill is an ever-so-slightly worse hitter than Verdugo. This is tempting. That was O’Neill’s only full season in the majors, and even in small sample sizes before and after he’s not been able to match that kind of production. You can tack that up to the injuries, which have been numerous, but that’s not exactly encouraging. If he’s hurt more often than he’s healthy, and that means he never plays as well as he can, then at a certain point that just means that the player taking the field is the version of him that you’re going to get. There’s no upside in an endless slew of rehab assignments.

There is, however, a second way to look at those numbers. For now, let’s set aside the injuries and just consider what he’s actually done when he has played.

Obviously, this looks bad. O’Neill is drastically down in batting average, OBP, and slugging percentage in his 600 plate appearances since 2021. However, I think there are quite a few reasons to be optimistic.

For starters, there’s a pretty big delta between O’Neill’s wOBA and his expected wOBA. At a very basic level this tells us he’s been unlucky with his batted balls falling in the last 2 years. A hitter with a .309 wOBA is a below average hitter. A hitter with a .334 wOBA (what statcast data projects his wOBA would have been with a more probable set of batted ball outcomes) is an above average hitter. That alone is reason enough to think O’Neill is still a valuable bat when healthy.

[A quick aside: I’ve seen a few people compare O’Neill to Adam Duvall since the Red Sox acquired him. Respectfully, that’s a bad comparison. O’Neill’s expected wOBA the last 2 years of .334 is a full 30 points better than Duvall’s .300 in the same time frame. That’s EXCLUDING the former Cardinal’s monster 2021 season. He also walks almost twice as often as Duvall, while impacting the baseball at a similar rate, making far more contact in the zone and striking out less. It’s the baseball equivalent of comparing a master carpenter to a lumberjack simply because both cut wood.]

That said, expected wOBA is not a perfect metric, and clearly something has gone wrong for O’Neill since 2021. Usually when metrics drop off across the board it means there’s been a change in approach. A common example of this is a player pushing too hard to do damage after returning from an injury, in turn expanding the zone, ultimately resulting in more strikeouts and weak contact.

That’s not what’s happening here either, though. If anything, O’Neill’s approach actually looks better than it was in 2021. He’s cut his strikeout rate down to a tolerable 26.2% and his walk rate has spiked from a pedestrian 7.1% to an excellent 10.1%. This is all a product of positive developments in other supporting metrics: the former Cardinals’ outfielder has cut down his chase rate while also increasing his contact rate on pitches in the zone by an astronomical 10% at the same time. Essentially, he’s more selective than he used to be AND has seemingly improved his ability to make contact drastically. These are usually things you say about players when they hit career highs, not career lows.

Now, there is a possible explanation for all of this: might O’Neill, in harnessing his newfound patience and contact ability, have compromised his ability to impact the ball? It is true that, not only has his contact rate in the zone gone up, but his contact rate outside the zone has as well. That’s the kind of change that can lead to weak contact, and as we all know, weak contact is bad. This would explain why his hard hit rate and barrel rate are down from 2021 as well.

This explanation ultimately falls short, though. O’Neill’s barrel rate of almost 12% since 2021 is still fantastic, and his 43.3% hard hit rate is still comfortably above league average as well. In summary, the guy is walking at career high rates and making contact in the zone at career high rates. As a result, he’s brought down his K rate to much more normal levels, all the while continuing to drive the ball. All of this is true, and yet his slash line looks downright pedestrian.

Once again, there are a few possible explanations for this. Platoon splits show that the gains O’Neill has made in terms of plate discipline and contact skills since 2021 are far more exaggerated against left handed pitchers than right handed pitchers. Perhaps because of this, an increasingly large share of O’Neill’s plate appearances have been against lefties since 2021. Further digging into the data also shows us that the outfielder has massively struggled against breaking balls during the same time period, with only 10 of his 55 hits coming against sliders and curveballs last season. I haven’t corroborated this with data, but I’d venture to guess these two issues are related: 2022 and 2023 have constituted The Dawn of the Planet of the Sweeper, and it’s easy to imagine the increased prevalence of the right-on-right sweeper in particular compromising O’Neill’s ability to identify and jump on pitches to drive against righties.

Even if we make that slightly fanciful jump, it does not change the fact that a) the evidence overwhelmingly points to O’Neill having been very unlucky with batted balls the last 2 years and b) this is a player in his 20s, 2 years removed from a top 10 MVP finish, whose approach and ability to impact the ball has not regressed to a concerning extent in any way in the intervening time. You simply cannot say any of those things about Alex Verdugo, and the newly minted Yankee hasn’t even managed to significantly out produce O’Neill at the plate in the two seasons wherein O’Neill’s been affected by Loud Out Syndrome (LOS).

So, to summarize, O’Neill is a better baserunner, fielder, and hitter than Verdugo. He’s also right handed, which is an attribute the Sox desperately needed in their lineup. The only edge Verdugo has in terms of ability here is, admittedly, key: availability. The Mexican national team member appeared in 493 of a possible 546 regular season games (90.2%) during his 4 years in Boston. That’s legitimate iron man stuff. O’Neill, in contrast, has only ever appeared in 477 games across his entire 6 year MLB career. If you exclude his rookie season, that’s about 59% of possible games. If you assume that’s the average outcome, then over the course of a season, even if you assume O’Neill is a 50% better player, that works out to more production from Verdugo than the new Sox outfielder. Playing games matters.

You might now ask: Kees, how are you so optimistic about this move if O’Neill’s availability issues are so pronounced? And my answer to that, dear reader, is that I just don’t care that much about average outcomes in the context of this deal.

The Red Sox need star players. Alex Verdugo is a perfectly good player, but he will almost certainly never put up an MVP caliber season. He’s a perennial 1.0–2.0 fWAR player. Those guys are nice for filling out rosters that are already teeming with stars. They do not make you contenders. While O’Neill is far more likely than Verdugo to give you absolutely nothing of value in a given season, he also has a very realizable chance of being a force at the top of a lineup. Even if that’s only a 20% chance, or a 10% chance, I’d prefer to have the upside that could make the team a contender over the consistency that makes them respectable basement dwellers. Sometimes building a team with a chance to win means building a team with a chance to lose, too.

Now, none of this really matters unless the Red Sox acquire star pitching. I, personally, don’t feel as jumpy about that as other Red Sox fans do. I’ll be surprised if they don’t come away with two good starters by winter’s end. Am I certain? No. But I’m cautiously optimistic, and for the time being I’m happy with the moves the team has made. O’Neill is a big part of that. Go Sox.