Article: Can Romy Gonzalez Be Mark Vientos?

[Davy Andrews]

Gonzalez hits the ball harder than just about any player on the Boston roster. How can the Red Sox turn all that power into run production?

The other day I was looking at some team leaderboards, and something jumped out at me. Maybe you already know this and maybe you don’t, but there’s one name at the top of Boston’s Statcast leaderboards that’s not like the others. Unsurprisingly Rafael Devers sits alone at the top in terms of hard-hit rate, average exit velocity, and 90th percentile exit velocity. In second place? It’s not Jarren Duran or Tyler O’Neill. It’s not even Wilyer Abreu or Triston Casas. It’s Romy Gonzalez. Romy Gonzalez, it turns out, is a threat to baseballs everywhere.

Player	EV	EV90	HH%
Rafael Devers	93.2	108.8	52.3
Romy Gonzalez	92.3	107.8	50.3
Tyler O'Neill	90.9	107.2	48.4
Jarren Duran	90.8	106.9	43.7
Rob Refsnyder	89.5	106.7	42.9
Wilyer Abreu	91.6	106.5	49.8
Triston Casas	90.2	106	45.2

Gonzalez is in his fourth season at the big-league level, and although he’s always pulverized the baseball, he’s never been able to turn any of that hard contact into actual production at the plate. However, the 2024 season was the closest he’d ever come. He was just a hair below average this season, but over the last three seasons with the White Sox, he ran an execrable 61 wRC+, and graded out as below replacement level. Frankly, the White Sox are the only organization in baseball that would let a player hit that badly for that long at the major-league level. Still, it’s easy to see why the Red Sox were willing to take a flyer on Gonzalez. Chicago isn’t exactly known for its success in player development, and even a small chance of figuring out how to unlock his potential was worth the risk.

I’d like to talk about why Gonzalez hasn’t yet been able to leverage all that contact quality, and to point to a hitter with a similar profile who did manage to figure it all out. As for the first part, the reason for Gonzalez’s struggles is plain to see. In a lot of ways, he’s the archetypal power hitter: he chases too much, he chases too many bad pitches, which leads to too many strikeouts and not enough walks. That’s not great, but there are still plenty of power hitters who have made that all-or-nothing approach work. Gonzalez has a bigger problem. His career groundball rate is 56.2%, miles above the league average of 44.4%. As the saying goes, there’s no slug on the ground. Until Gonzalez figures out how to turn a groundball into a homer, he’s going to keep wasting his greatest gift.

Gonzalez had a 90.2 mph average exit velocity on groundballs this season, which ranked 27th in all of baseball (minimum 20 GB). That puts him in the 94th percentile. On fly balls, he had an exit velocity of 92.7 mph. That sounds better, but here’s the thing: everybody hits fly balls harder, so Gonzalez was no longer near the top. He ranked 167th in baseball, all the way down in the 61st percentile. In other words, the problem is not just that Gonzalez puts the ball on the ground too much, it’s that his swing is geared toward groundballs rather than fly balls. When he squares the ball up, he’s not putting it in the air where it can do damage. Let me show you what I mean.

 

The charts above are from Statcast, and they break down Gonzalez’s career launch angle in two different ways. On the left is his average exit velocity, broken down by the angle. As you can see, the graph is at its very highest a bit below zero degrees. In other words, Gonzalez’s swing works in such a way that when he is really crushing the ball, he’s hitting a low line drive or a hard groundball. When he’s hitting the ball between 20 and 35 degrees, where extra-base hits happen, he’s not making his best contact. The graph on the right breaks things down by frequency. The gray area is all of his batted balls, and the red is just the ones that fall in for hits. Even though the graph on the left shows us that Gonzalez really smashes the ball at just below zero degrees, he's not getting any hits there. There just aren’t many hits to get; those end up as groundball outs, even when they’re hit hard.

All of this brings me to two players in the Mets organization. Mark Vientos and Brett Baty are both third basemen, and they both laid waste to the minor leagues before struggling mightily in 2023 and 2024. Like Gonzalez, they had plenty of power, but they ran groundball rates over 50%, and as a result, their wRC+ stayed in the 60s. Baty still hasn’t figured things out, but this season, Vientos dropped his groundball rate to 44.2%. That’s still a pretty high, but it was enough to completely turn things around. This season, he ran a 133 wRC+ and was a key contributor to New York’s playoff run.

Obviously, the Mets were aware of the problem facing Baty and Vientos, but for whatever reason, they were only able to help one of them solve it. There’s nothing easier than identifying players who need a swing change, but it’s a whole lot harder to implement one successfully. Plenty of players never figure it out, and for Gonzalez, who just turned 28, it’s awfully late in the game for such a radical change. Maybe he’ll never unlock the full potential of his swing, but I would like to propose one specific way that he might try it.

Earlier this season, Major League Baseball released bat-tracking data for the first time. I dove into the numbers and wrote several articles about it, but one in particular is more relevant to Gonzalez’s situation. Gonzalez has a career 33% pull rate, which is extremely low. I made the graphic below. You can ignore the numbers, but keep an eye on the bat angle. The point is that the further out you hit the ball, the more likely you are to pull the ball, because your bat will be angled toward the pull side.

Because of his extremely low pull rate, we can be certain that Gonzalez isn’t going out and attacking the ball in front of the plate; he’s letting it get deep in the hitting zone.

One of the things that the launch angle revolution taught baseball nerds is that when a player hits the ball out in front of the plate, they also tend to lift it more. Here’s what I wrote at the time: “In any but the most dramatic of old-fashioned, chopping-wood-style swings, attack angle will drop at the beginning of the swing, then increase toward the end. To illustrate that down-up-down path, I slowed down a Statcast video showing Oneil Cruz’s bat path on a recent line drive.”

If you hit the ball out in front, your bat will be traveling upwards when it meets the ball, making a higher launch angle more likely. If Gonzalez were to keep make a real effort to meet the ball out in front, he might be able to lift the ball without radically changing his swing. I’m not saying that Gonzalez could suddenly turn into a star like Vientos; there’s likely too much swing-and-miss in his game for that no matter what. But he still has the potential to be a real run producer. No matter what happens, this will be an extremely important offseason for Gonzalez. The Red Sox are planning on adding to their roster and returning to contention. They could certainly use a right-handed power bat, but if he can’t figure out a way to contribute to that effort, he’s unlikely to last very long. It’s time to see whether he can finally unlock his potential.

View full article

[notin]

So how many are glad this thread turned out to be incorrect and Romy Gonzalez (.955 OPS) has NOT turn into Mark Vientos (.623 OPS)?

[TedYazPapiMookie]

Gonzalez is either a very slow learner or he's having a career year.  All the metrics in the world won't predict his future.   Trending his skills makes you think it could be he's developed slowly from a mediocre college career or moving to Boston helped him develop faster but there isn't enough data to feel comfortable picking the likely future of Gonzalez.  You keep him another year and hope this 2025 season isn't an anomaly.   Based on his mid-season performance, I believe he will regress to the mean rapidly in the second half and what we thought about his overall skills in Spring Training will probably be proven out by the end of the season.  If that's the case, don't be shocked if he hits around .200 the rest of the season.  Also don't be shocked if he maintains his current performance.  With so little data to go on, his second half performance has a wide range of possible outcomes.  

All the metrics provided in the article are fun to look at but worthless at predicting the future.  That's the nature of metrics.  Great toy, no predictive value.  Flip a coin or guess is just as accurate but like I said if you are into numbers, inaccurate what-if numbers are always fun to review.