Last Saturday, Willson Contreras hit this opposite-field homer off an Anthony DeSclafani slider. Thanks to the soft skin of home plate umpire Gary Gibson and the Cubs ultimately falling for the third straight time to the last-place Reds, Contreras’s second-inning shot was nowhere near the most newsworthy thing that happened in that game.
But the home run was an important one for Contreras. Not because of the authority with which the ball was hit; it just barely edged over the short right field wall of Great American Ball Park. It was close enough that the Reds asked for an umpire review, claiming fan interference.
No, this home run was important because it was Contreras’s first since May 12th, a span of 31 games. Amazingly, it was Contreras’s first home run against a National League opponent since August 6th of last season, a streak of 72 games (all four of Contreras’s home runs this season prior to that game had come during interleague play). While his struggles in the power department haven’t gotten the publicity of Kris Bryant’s homerless streak earlier this year, it’s been hard to ignore Contreras’s deficiencies in the power department. Just a few weeks from the All-Star break, he has five home runs, tied with Ben Zobrist for sixth on the team. And while Zobrist has had a resurgent year, anyone who witnessed Contreras’s phenomenal first two years in Cubs pinstripes had reason to expect more slugging out of the 26-year-old backstop.
But don’t be fooled: Contreras is the best he’s ever been as a hitter.
First, let’s address the home run drought. Contreras put the ball in the seats an incredible 31 times in his first 191 games in the majors; the only Cubs in history with more to start their careers were Kyle Schwarber (44) and Kris Bryant (35). But a peek below the surface would have revealed that, while his power is real, it may not be the transcendent power he’s flashed during his high points.
Over the past few years, around 12 percent of balls put in the air have resulted in home runs. Contreras, by contrast, homered on 25 percent of of his fly balls in 2016 and 2017. While HR/FB rates vary based on the hitter (which is intuitive – one can’t expect Tommy La Stella and Anthony Rizzo to homer at the same rate on balls hit in the air), expecting Contreras to homer one out of every four times he puts the ball in the air is asking a lot.
A few hitters throughout MLB history have managed to maintain HR/FB rates of 25 percent. Three of them, in fact: Giancarlo Stanton, Ryan Howard, and Jim Thome. So while there’s nothing wrong with enjoying this, or this, or this, there is a significant difference between enjoying the thing and expecting the thing to continue indefinitely. Contreras was always going to hit fewer home runs moving forward.
This year, though, Contreras’s fortune has swung the other way, with just 6.3 percent of his fly balls leaving the yard, a figure that ranks 134th of 160 qualified hitters, below the likes of light-hitting Eduardo Nunez and Billy Hamilton. Contreras’s power, it seems, has had a pendulum-like trajectory. He’s gone from an unsustainably high HR/FB rate in his first two years to an unsustainably low one in 2018. This may seem like a boring, or safe, or obvious explanation, but Contreras’s power is likely in the middle of these two extremes.
There is, however, a certain irony in Contreras’s sudden drop in HR/FB rate this year, and it’s this: he’s actually trying to hit more home runs than he has in the past.
For the first two years of his career, Contreras was, for the most part, a ground ball hitter (a fact that was easy to forget given the sheer volume of both home runs and subsequent bat flips he was responsible for). In both 2016 and 2017, Contreras hit the ball on the ground 54.3 percent of the time; league average in each of those years was around 44 percent.
This year, though, Contreras seems to be making a concerted effort to elevate the ball. Take a look at his year-to-year batted ball data, with the launch angle and exit velocity numbers pulled from Baseball Savant:
| Year | Fly Ball Rate | Ground Ball to Fly Ball Rate | Average Launch Angle | Average Exit Velocity |
| 2016 | 17.7% | 3.06 | 5.9° | 87.8 MPH |
| 2017 | 16.7% | 3.26 | 5.9° | 87.1 MPH |
| 2018 | 20.2% | 2.55 | 9.0° | 88.4MPH |
While Contreras seemed to be the same hitter in 2016 and 2017, this year has brought a more fly ball-heavy approach. Contreras is hitting more fly balls, and he has raised his average launch angle by more than 50 percent this year, all the while increasing his average exit velocity. One would think these shifts would lead to increased power production. Instead, Contreras has seen a considerable slide in the power department, a cruel reminder that it’s not as simple as Launch Angle + Exit Velocity = Home Runs. It’s baseball; there’s always more to the equation.
Even despite the changes Contreras has made to his approach, it is possible that Contreras is more of a 15-20 home run player than a 20-25 one (and in fact, PECOTA’s 50th percentile projection of 11 home runs seems a lot less crazy in late June than it did before the season began). But even if we accept that Contreras may have already peaked from a power standpoint—which, to be clear, I’m not ready to do, as there’s still plenty of time for him to grow into more power—there is substantial evidence that the young catcher has matured as a hitter in his third year. Take a look at his plate discipline numbers over the past three seasons:
| Year | Contact Rate | Zone Swing Rate | Zone Contact Rate | Outside Zone Swing Rate | Outside Zone Contact Rate | Swinging Strike Rate |
| 2016-2017 | 69.1% | 64.7% | 78.0% | 32.3% | 54.3% | 30.1% |
| 2018 | 74.7% | 68.9% | 82.4% | 29.5% | 58.3% | 25.3% |
The above chart isn’t difficult to decipher, but I’ll break it down: Contreras is making significantly more contact overall, largely because he’s swinging in the zone more and chasing pitches outside the zone less. Even when he is tempted by a pitch outside, he’s done a better job making contact. On top of all that, his swings and misses have dropped precipitously.
All of this is very, very good for Contreras’s outlook as an overall hitter.
Thankfully, we’re beyond the days when we’ve got nothing but the “back of the baseball card” numbers to define a hitter’s progression. In some other era, Contreras’s seeming lack of power in 2018 might be viewed as him taking a step back, or worse, as pitchers “figuring him out” in his third year in the big leagues. The reality is that Contreras has made all sorts of improvements that are not shown in the box score. For now, let’s forget about the fact that he only has five home runs on June 24th, and realize that Willson Contreras is a better hitter than he was a last year, or the year before that. And if his work ethic is what it appears (after all, this is a guy who transformed from third baseman to one of the best catchers in the game in just a few years), Contreras will be even better in the years to come.