It’s finally happening.
After years of playing second fiddle to the likes of Yadier Molina, Willson Contreras, and, for some reason, Pedro Pagés, Iván Herrera is being given the spotlight as the Cardinals’ backstop. Now several years removed from being crowned the heir apparent to Molina, Herrera has gotten off to a scorching hot start in 2025. The 25-year-old is crunching the ball, with four home runs in seven games and a slugging of 1.048.
Herrera didn’t come out of nowhere, but 2025 is shaping to be a breakout year for Herrera, who looks to stake his claim as the best catcher in baseball.
Big Swinger
Through the first week of the season, it seems like Herrera has added about a tick on his swing speed (is it weird to say “tick” for hitters?).
Source: Baseball Savant
Hardly a seismic shift, but it’s an important element to his improvements. As you might expect, his exit velo has been higher as a result – with one element particularly interesting:
The higher exit velocities are nice, but it’s the exit velocity on fly balls that I want to focus on. When Herrera has hit a ball in the air, it’s been crushed. It’s not sustainable – far surpassing the fly-ball exit velocity of even Aaron Judge – but if you want the short answer to why Herrera has been off to such a good start, it’s because he’s been capitalizing on his opportunities.
Herrera has been trying to create more opportunities by being more aggressive in the zone. Swing aggression is a fickle thing, but swinging at pitches in the heart of the zone is pretty much always good. In 2024, Herrera was quite passive in the heart of the zone, swinging just 66% of the time. So far in 2025, however, Herrera has jumped on these pitches 84% of the time. Given how early it is in the season, how sticky this new aggression will be is highly questionable, but with Herrera’s strong contact ability and generally good outcomes when he does swing, being aggressive is a welcome change. It hasn’t affected his whiff rates early in the season either, whiffing just 15% of the time. Not giving your pitchers free strikes is a surefire way to put yourself in advantageous positions.
Short N’ Sweet
In June of last year, Iván Herrera went on the IL with back tightness. When he came back in late August, he immediately started raking, posting just shy of an 1.100 OPS in September and October. Hitting .381 with four doubles and two home runs, Herrera finished incredibly strong to end the year, making me take notice back in October. So what prompted this change? Well, take a look at three pictures, first from April, then in June, and finally one from September of 2024:
April
June
September
I spot several key differences here:
- Herrera’s bat position has progressively moved back significantly, from leaning over the plate to tilting back slightly.
- His elbows are less outstretched, cocked in near his ribs as opposed to hanging out over the plate.
- He’s moved up closer to the plate to compensate, look how you can see his back foot is closer to the chalk of the batter’s box
- His stance has opened up considerably. You can almost see the ‘4’ in ’48’ on the front of Herrera’s jersey, while in the April shot, you can barely see the 8.
So what do we make of this? Well, on points 1 and 2, it seems like Herrera has tightened up his swing, which we can see from Statcast data on month-by-month swing length:
| Month | Swing Length |
|---|---|
| Mar/Apr | 7.8 |
| May | 7.6 |
| Jun | 7.4 |
| Aug (only 4 games) | 6.9 |
| Sept | 7.2 |
For reference, 7.8ft is the same average swing length as Paul Goldschmidt, whereas 7.2 ft is the same as Ozzie Albies. This shortened, more compact swing could explain why Herrera’s whiff rates went from 27.4% in March and April to 23.1% in September.
The fourth point is perhaps most interesting. Remember how Herrera hit the IL due to back tightness? Well, look at his stance once he returned from the IL. Courtesy of Statcast’s new batting stance feature, we now know that Herrera opened his stance up considerably from 30-35 degrees to 44 degrees in September. That came with a more exaggerated leg kick, which suggests to me that Herrera is using his legs more the generate power than his back. Here are those earlier stills in GIF form, just to show you what I mean:
To me, it seems clear that the second swing is much shorter with much less back action than the swing from April. While Herrera ended up sacrificing a bit of bat speed for this change, he whiffed far less and made considerably better quality of contact overall. It seems his cutting down on the more erratic elements of his upper body movements has helped him to have greater barrel control, leading to stronger results.
New Jack Swing
Coming into 2025, Herrera had a chance to be the number one option at catcher for St. Louis.
Savant data shows that Herrera has an average swing length of 7.6 ft, which suggests that his swing hasn’t shortened, but examining the zones of his actual swings is more revealing. Herrera has faced a higher percentage of pitches low than in 2024, naturally elongating his swing. A longer swing does create more bat speed, but in the center of the strike zone, where Herrera’s swing length is slightly shorter than in 2024, he added two mph to his bat speed, matching the overall bat speed increase mentioned earlier.
This means that in 2025, Herrera has thus far kept the shortened, tighter swing, but with more power behind it. The tape shows that he’s kept his “new” swing, too. Take a look at these two swings:
Take note of the hand position, the leg kick, and the stance. Here’s the Statcast data showing Herrera’s swing stance in 2024 and his stance at the beginning of 2025:
Source: Savant
So the swing Herrera exhibited at the end of 2024, which saw him perform better than he ever has, has stayed going into 2025. Furthermore, he’s been more aggressive in the zone while keeping his chase rates down. All together, Herrera has made considerable improvements over the last calendar year that has shown that no, this is not a fluke, and that Herrera’s hot start is legit.
IL The Terrible
When I started writing this article, I was very eager to jump on what was looking like a player in the midst of a breakout. Herrera then suffered a bone bruise on his left knee. It should only keep him out a month, but it really sucks. Herrera’s new swing relies on a bigger leg kick, so if he’s uncomfortable with his front leg… that power stroke may evaporate quickly.
BUT if he makes a full recovery then Herrera may come back with the early April hype mostly dissipated. If so, he could be a TREMENDOUS buy, as Herrera is poised to be the best offensive catcher in baseball.
