William Contreras Is a Superstar

How an overlooked younger brother became my favorite catcher in baseball

William Contreras’ 2023 was one of the best ever by a Brewers catcher. Among all backstops to play in Milwaukee since 1969, Contreras finished 4th in wRC+, 4th in fWAR, 1st in runs, 6th in HR, and 4th in RBI during his debut season with the franchise.

If we use Baseball Reference’s version of WAR and limit our Stathead search to Brewers catcher seasons that had an OPS+ of 125 or above, then Contreras’ year becomes even more impressive:

(For the youths out there, Ted Simmons is a Hall-of-Famer).

How did Contreras become so good so fast? Why did the Brewers even end up with him? And how did he have consecutive All-Star-worthy seasons that were accomplished differently?

We must first go back to Atlanta in 2022 to answer these questions.

The Younger Brother

It’s funny to look back on Contreras’ past two seasons and see that he was an All-Star in 2022 but not 2023.

Contreras debuted with the Braves for four games in 2020, posted an 87 wRC+ (185 PAs) as a rookie in 2021, and then broke out during the first half of 2022.

While splitting time with Travis d’Arnaud behind the plate that year, in addition to some left field and DH work, Contreras recorded a 139 wRC+. He smacked 20 homers in just 97 games, striking out close to 28% of the time but doing so with a 91st-percentile barrel rate.

Contreras wasn’t initially part of the Braves’ plans, but he received more of an opportunity once Manny Piña was lost for the season in early May. The 24-year-old became such an offensive force that he was named a reserve for the National League All-Star team. Once Bryce Harper went down with a thumb injury, William was chosen as the team’s starting DH.

He and Willson became the first brothers to attend an All-Star game together since the Boones in 2003. With Willson voted as the senior circuit’s starting catcher, the Contreras duo became the first brothers to each start in the same midsummer classic since the Alomars in 1992.

For a while, this was the William Contreras story — a fun one about a so-so catching prospect who was signed out of Venezuela for just $10,000. He happened to be the younger brother of an established big leaguer. A combination of poor defensive metrics and expected regression on offense meant we might’ve seen the peak of it. This is when the Brewers somehow got involved.

A New Approach

Here’s what each team received in the A’s/Braves/Brewers Sean Murphy blockbuster:

• Braves get: Sean Murphy

• Brewers get: William Contreras, Joel Payamps, Royber Salinas

• A’s get: Esteury Ruiz, Kyle Muller, Freddy Tarnok, Justin Yeager, Manny Piña

Why Oakland didn’t just ask Atlanta for Contreras as part of the Murphy return is beyond me. Even crazier is that the only player Milwaukee gave up in this 9-player, 3-team trade was Esteury Ruiz.

It was puzzling at the time. 14 months later, even more so.

Regardless, the Brewers pulled off a heist, and Contreras was set for a starting role for the first time in his career.

There was no doubt Contreras had power entering 2023. After he led catchers with a 139 wRC+ in 2022 (min. 375 PAs), the question was whether he could sustain an elite barrel rate with so much swing-and-miss in his profile.

And then this happened:

Contreras’ K% gains were fueled by a reduction in chase rate and a spike in his contact rate.

Impressively, Contreras did more than suddenly stop swinging. His Z-Oswing% improved from 34.5% in 2022 to 36.2% in 2023.

That still isn’t an above-average mark, but it shows his knowledge of the strike zone improved.

This is where a stat like SEAGER becomes really interesting. If you haven’t done so already, I highly recommend Robert Orr’s Baseball Prospectus article on it. Using his numbers, Contreras was in the 28th percentile for Z-Oswing% in 2023. SEAGER, which focuses on a hitter’s ability to recognize the pitches he can do damage with, places him in the 85th percentile.

Robert’s numbers show that Contreras had an elite “selection tendency”, meaning he wasn’t letting pitchers beat him. This stems back to the dramatic chase rate improvement.

In the following two spray charts, it’s clear that Contreras did himself a favor by better utilizing the entire field. Look at all those hits to right field in 2023.

This combination of skill improvements is how William held off regression to post a 124 wRC+, the fourth-highest among backstops in 2023. He also ranked 2nd in PAs, 1st in runs, 4th in RBI, 1st in AVG, 2nd in OBP, and 3rd in OPS.

The only bummer was that Contreras’ barrel% fell off more than expected, down to the 58th percentile. This caused his xSLG to drop. Combined with some “over-performance” of his expected stats, this is probably why THE BAT X is a little cooler on its projection than some other systems for 2024.

Of course, this might be the trade-off with fewer strikeouts.

If Conteras maintains this approach in 2024, he’ll remain a top-5 catcher in baseball. If he marries his newfound selectivity with the high-end ability to barrel that he flashed in 2022, then we might see one more level unlocked from him this season.

The Catching Lab

On top of all of this, Contreras became an exceptional defensive backstop.

Foolish Baseball notes in this delightful YouTube video that the organization has a history of improving catcher defense.

If you’re interested in exactly how Contreras improved, I recommend this Fangraphs article from Esteban Rivera.

Here are the year-end results for Contreras’ defense, which Esteban touches on in his piece:

By fWAR, he was the most valuable catcher in 2023. It was the eighth most valuable catcher season in the Statcast era (since 2015).

The coolest part is that Contreras did it differently than he had in 2022. That ability to adjust his game at such a young age shows we may not have seen the best of him yet.

That’s why he’s my favorite catcher in baseball. He’s young, established, and possibly still underrated. I can’t wait to see how he performs in 2024.