This Time, Ronald Acuña Jr. Is Back
Sometimes there’s a difference between returning and being back. After tearing his right ACL in July of 2021, Ronald Acuña Jr. returned on April 28, 2022. He put up a solid 2.1 WAR over 119 games, a 2.9-win pace. Think of him as Paul McCartney in 1970, releasing the solid but uninspiring McCartney on the heels of a regrettable rupture. This year, Acuña is back. He’s Paul McCartney in 1971, authoring an all-time classic in Ram. Please don’t examine this metaphor any further because it can’t stand up to scrutiny (but please give Ram a listen because it can).
Acuña has put up 4.9 WAR and a 166 wRC+ and racked up outfield assists on throws beautiful enough to make an angel cry (or a Cardinal, or a Padre).
Acuña is slashing .335/.412./.589, and for what it’s worth, his 166 wRC+ might be the result of a bit of bad luck. His .459 xwOBA is 34 points higher than his actual wOBA. It’s also the highest in the league, even higher than You Know Who.
Over at Baseball Prospectus, Robert Orr pointed out that Acuña has more confidence in his knee. He’s getting deeper into his batting stance and putting more weight on his back leg than he did last year, allowing for a more explosive swing. He’s swinging less both inside and outside the zone, forcing pitchers to throw more strikes even though he’s hitting the ball harder than ever. If the season were to end today, Acuña’s 94.9 mph average exit velocity would be tied with 2017 Aaron Judge for the eighth-highest ever recorded.
Inside the zone, it’s not just that Acuña is swinging less; he’s also focusing more than ever on the inner half and eschewing the outside corner altogether. On the left is his swing rate over the course of his career, and on the right is his swing rate this season.
Focusing inside and down has raised his groundball rate, but as Orr noted, it’s also allowed him to meet the ball out in front of the plate, driving the ball to the pull side and halving his popup rate.
Acuña is taking more strikes this year, but he’s making up for it by whiffing way less. He’s cut his strikeout rate by an astonishing 11.5 percentage points, from 23.6% to 12.4%. I checked strikeout rates all the way back to 1900; excluding the shortened 2020 season, only two qualified players have ever dropped their strikeout rate by 10 percentage points:
| Player | Year | Year 1 K% | Year 2 K% | Difference |
|---|---|---|---|---|
| Mark Belanger | 1968-69 | 21.5% | 9.1% | -12.4% |
| David Ortiz | 2010-11 | 23.9% | 13.7% | -10.2% |
Acuña’s play has been so remarkable that any article about him is in danger of devolving into a list of fun facts.
- Did you know that when Acuña’s at the plate, outfielders play deeper than they do for anyone else in the league?
- Did you know that he recently set a modern era record by either homering or stealing a base in 13 consecutive games?
- Did you know that, going by Baseball Savant’s run values, Acuña is the only player who’s been a net positive against every single type of pitch they’ve faced? Even Luis Arraez, who strikes out roughly once every time they release a new Fast & Furious movie, has negative marks against sweepers and slurves.
But Acuña’s hitting is not necessarily our topic for today. Over at The Athletic, Jayson Stark handed him the first-half NL MVP trophy and noted that Acuña isn’t just trying to join the 40–40 club; he’s trying to found the 40–75 club.
Acuña has stolen 41 bases, 15 more than Corbin Carroll, who’s second in the NL. (Carroll has a solid case as best baserunner in the game, but that’s also not our main topic.) The only way Acuña wouldn’t win the NL’s stolen base crown is if he gets injured or if Elly De La Cruz decides to continue stealing bases three at a time.
Acuña is also just two behind American League leader Esteury Ruiz, giving him a real shot at the MLB title. (In depressing news, Ruiz just hit the 10-day IL with a right shoulder subluxation, which might make Acuña’s path to the MLB crown even easier. Carroll had his own right shoulder scare, but he hasn’t missed a game and seems to be okay.) Acuña is currently on pace for 75 steals, and if he were to make it, he’d be the first player to hit that mark since Jose Reyes in 2007.
There are those who will argue that Acuña’s stolen base totals mean less this year due to the new rule changes. I don’t agree, but I’m less concerned about the actual numbers. I care about Acuña’s thieving prowess relative to the league because he has an excellent chance of winning the National League MVP and the stolen base crown in the same year. Depending on your preferred flavor of WAR, Acuña has thus far been 0.6 and 1.8 wins better than any other player in the NL, and he’s leading the best team in baseball. He’s the obvious front-runner.
No one has taken home both an MVP and a stolen base crown since 2001, though there have been some close calls in recent memory. You could make an argument that Trea Turner deserved to win the NL MVP when he stole 32 bases in 2021, and just about everybody with an internet connection made the argument that Mike Trout deserved the AL MVP when he stole 49 bases and put up 10.1 WAR in 2012. Regardless, here’s the complete list of players who have actually achieved this particular bifecta since they started awarding MVP Awards (or their equivalent) in 1911:
| Player | Year | League | SB | WAR | Led MLB? | Hall of Fame? |
|---|---|---|---|---|---|---|
| Ichiro Suzuki | 2001 | AL | 56 | 6 | Yes | Yes |
| Rickey Henderson | 1990 | AL | 65 | 10.2 | No | Yes |
| Maury Wills | 1962 | NL | 104 | 5.3 | Yes | No |
| Jackie Robinson | 1949 | NL | 32 | 9.6 | Yes | Yes |
| Frankie Frisch | 1931 | NL | 37 | 4.1 | No | Yes |
| Eddie Collins | 1914 | AL | 48 | 8.3 | No | Yes |
That’s a list of six players, five of whom have their faces on bronze plaques upstate. Ichiro is the only player to win the MVP and lead the league in stolen bases in the last 40 years. We might be due, as this feat happens roughly every 18 years. Still, Acuña is on pace for 9 WAR, more than four of those Hall of Famers, and 75 stolen bases, significantly more than all of them.
The interesting thing is that Acuña is actually slower this year than he’s ever been. His 28 mph sprint speed is down from 28.5 last year, and his career high of 29.7 as a rookie. His home-to-first time is 4.31 seconds, up from 4.27 last year and 4.1 as a rookie. His speed is still above average compared to the overall player population, but right around average for an outfielder.
In some ways, Acuña is the perfect player for this moment. If you’ll recall the sudden juicing of the baseball back in the mid-2010s, players with middling amounts of pop were the biggest beneficiaries. The Giancarlo Stantons of the world don’t need a few extra feet of carry to hit home runs, and the Nick Madrigals need a lot more than a few extra feet. The Francisco Lindors were the ones who saw warning their track power turn into home run power.
This isn’t a perfect comparison, because in this year’s friendlier stolen bases envirement, steals are up among all players except the very slowest. Still, Acuña finds himself in a similar sweet spot. He’s no longer a burner, but he doesn’t need to be to clear this new lower bar. Above-average speed is plenty, especially when it’s possessed by a veteran with seasons of 29 and 37 stolen bases under his belt.
This opportunity gets combined with two factors. The first is that Acuña is always on base: His .412 OBP is third in baseball, and per Baseball-Reference, his 167 times on base lead the majors. Per Baseball Prospectus, he’s is second to Ruiz with 44 stolen base opportunities and second to Steven Kwan with 167 baserunning opportunities.
The second factor is very simple: Acuña just wants to run. Here’s what he told Jordan Shusterman in June: “Once I regained myself and got back to where I wanted to be, I just told myself that I was going to steal as many bases as possible.” Turns out that was a pretty good plan. At this point, when Acuña decides he’s going to do something, we should probably assume that he’s going to do it.
Davy Andrews is a Brooklyn-based musician and a writer at FanGraphs. He can be found on Bluesky @davyandrewsdavy.bsky.social.
Here’s another extremely fun fact. This season, after reaching an 0-2 count, Acuña has a .950 OPS. As someone who sees as many of his plate appearances as possible, he really seems to take that count as a challenge and changes his approach to avoid striking out–and yet he still slugs .559 after reaching 0-2. Who on earth is this guy?
Not to be agressively pedantic, but Ichiro isn’t yet in the HoF, so it should be only 4 of 6 in that table are in the HoF. (Not a question of worthiness, just that he hasn’t hit the 5 year mark/been elected/etc. Everyone knows he’ll be in.)
This is interesting, but the stolen bases are more like the gourmet dessert than the main meal here. It’s pretty clear what makes Ronald Acuna so good (and the deserving MVP winners listed on the “bifecta” table, so, not Maury Wills) is getting on base. Acuna is tied for third in OBP, and doing it the old fashioned way, by not striking out and scorching balls when he hits it. You don’t get nearly as many opportunities to steal if you’re not on base, and he’s been on first base a lot (and second base too, lots of doubles there). Acuna is somewhere between Rickey Henderson (who was the best base stealer of all time but his foundation was getting on base, a more extreme version of the phenomena here) and Ichiro (who got on base a bit less and is stealing less than Acuna is doing, but the same thing still applies). You eat your dinner (getting on base), you get your dessert (a chance to steal the next one).
Esteury Ruiz is a different sort. He has only wound up on first base 92 times, compared to 122 for Acuna (fewer doubles too, although it’s less extreme). But he’s running virtually every single time he gets on base. The difference between 122 and 92 doesn’t seem like that much, but it becomes more obvious when you compare it with steal attempts. With the caveat that you can steal from second base too (so, if you wanted a true denominator that would be base states and not times on first base) the ratio of 1B outcomes to steal attempts is 2.5:1 for Acuna and 1.8:1 for Ruiz. That’s nuts; it means that if Ruiz gets to first base, he is running. This isn’t Rickey Henderson, this is Vince Coleman.
Not to quibble too much with your assertion, because Rickey is my favorite player ever, but I’d argue Raines as the best with Rickey as the most prolific. Anyone who can slide into a base and not break a glass vial in their pocket wins.
Hot take: “Ram” is better than the last Beatles album.
Wills had 5.3 WAR in 1962. 🙂
And perhaps more importanty, 104 SBs!
Thanks so much for catching these! Pulled in his 1961 stats by mistake. They’re fixed now.
Yep, looks like Maury’s 1961 stats got substituted by mistake. That was quite a year-over-year improvement! His PA’s rose slightly from 687 to 759, while his OBP only ticked up from .346 to .347. It would seem that he just started stealing nearly every bag in sight.
Yes, overall performance is back; however, it is not the same R. Acuna, Jr. as in 2021. He has made a significant swing change and in the process and has traded some contact quality to get a lower K rate. His attack angle – which was top quartile in 2021 is now bottom quartile. As a result, he has the 16th highest GB% in the league and 17th lowest average LA. His VBA which was also top quartile in 2021 is also down significantly. His barrel rate of 15% is well off the 20% in 2021
So while he’s hitting the ball significantly harder this year, it looks like his contact quality (ex the EV increase) is closer to last year than 2021. While many may see this as a good trade-off to get the lower Ks, it seems likely that he’s improved his K rate from other places in addition to the flatter swing…which suggests there is still some upside in him getting some of his ‘old’ swing back.
Who knows if this is why, but as someone who really believed Acuña could go off stealing bases with the new rules (pitchers were able to wear him out as he had a tendency to dive back to first on almost all pickoff attempts, so pitchers could throw over a lot and then he’d either not run or his attempts would be slowed), it could be a more valuable trade-off of power for average when you are constantly standing on second after singles anyway.
It’s also pretty impressive to give up power for contact and still be on pace to break the leadoff RBI record.
He really does hit the shit out of the ball, so even a little loft would make 40 Home Runs more likely. I personally notice he gets a lot more contact on high fastballs but like as not they’re just really hard grounders.
I think Acuña’s speed decline could be a little overstated based on sprint speed. Acuña has been asked (both last year and this year) to try to be judicious about when to turn it on to 100. Even on SB attempts, to the naked eye, he looks like he is often still in 4th gear. There is also at least a bit of statistical backing for this theory. Acuña has 11 bolts this year (sprint speed recorded over 30.0). Looking at the 17 players with at least 8 bolts (yes, this is cherry picked), his sprint speed is 0.6 lower than 16th on this list. The “he generally holds just a smidge back” theory would explain this.
If you don’t cherry pick, only 2 players with at least 2 bolts have lower sprint speeds than Acuña. Tim Anderson has 7 bolts and a 27.2 sprint speed (which might be ever more of an outlier than Acuña) and Starling Marte has 2 bolts and a 27.1 sprint speed.
Also, note that if you rely solely on sprint speed, Austin Riley is faster than Ronald Acuña. Anyone want to make that claim? Anyone???
FWIW from the eye test, this seems to be true. I feel like in previous seasons, he went all out on every soft grounder and this year, that just largely isn’t the case.
IIRC Adam Duvall was the fastest player in the league or something? Maybe faster to full on a fly ball?