The Brewers Don't Care About Your Sweeper Revolution

Since the dawn of the pitch-tracking era, and especially since Statcast and the data it generates began to inform pitching development in 2015, MLB teams have steadily become more reliant upon breaking balls--especially sliders. The primary driver of that trend is the pursuit of swings and misses, which the slider gets at a higher rate than any other offering. Thus, we shouldn't be surprised that the young 2023 season has only seen the march toward slider hegemony continue, as teams adjust to new rules that make opponent contact more dangerous.

Slider and Sweeper Usage by Season, MLB, 2015-23

The hottest pitch in baseball this spring has been the new version of the slider, dubbed the sweeper, which has only made it easier for the league to increase its use of the pitch. A sweeper is just a slider with greater horizontal movement and less vertical movement--a big-breaking cutter, in one way of viewing things, or what would have been called a roundhouse curve back in the first half of last century. Hardly anything in baseball is truly new, and the sweeper is far from being an exception to that bit of wisdom, but the eagerness with which many teams, players, coaches, and fans have embraced the concept of the sweeper as a new and distinct pitch only highlights the desire of everyone in the MLB orbit to ratchet up slider usage and utility by whatever means.

The Brewers have a couple of purveyors of the sweeper. Colin Rea has used it to miss a surprising number of bats since being called upon to fill the unexpected void left in the rotation when Brandon Woodruff went down. Rea has introduced his sweeping slider against right-handed batters, at the expense of the curveball he used to prefer, and it's yielded solid results. However, it's not the most notable change he's made.

Rea's switch from leaning on a four-seam fastball to being primarily a slinger of sinkers is telling. The above is just his pitch usage against right-handed batters. (Always analyze pitchers' repertoires by first isolating their work against lefties and against righties; the two tasks that make up pitching overall are distinct and need to be treated that way.) Here's what he's done against left-handed hitters.

It would be hard to overstate the extent to which the Brewers' approach with sinkers is bucking the league norm. I wrote this weekend about the fact that Peter Strzelecki has not only added a sinker to his arsenal this spring, but used it fairly often against left-handed batters. Few teams in baseball instruct their pitchers to use their sinker against opposite-handed hitters, unless it can't be helped. The Brewers are an exception. Just as importantly, here, note that Rea has become primarily a cutter guy against lefties. That's more conventional, but equally telling. The Brewers love sinkers and cutters. They want hard stuff with late movement, the kind that limits the quality of opponents' contact and lets the team's league-best defense do its job. They want the good control that comes with throwing fewer breaking balls and more of what amount to fastballs.

As a result, only one team in MLB has thrown fewer sliders and sweepers than the Brewers in 2023.

Sliders and Sweepers as Percentage of all Pitches, Top and Bottom 5 MLB Teams, 2023

Even Rea, the rare Brewer who has developed a new slider this year, helps illustrate what the Brewers prefer to do instead. Strzelecki's new sinker tells a clear story. The fact that the team elected to bring back Wade Miley via free agency is telling. With Corbin Burnes as their ace, the pitching staff really seems to have taken on his identity and learned the lessons implied by his breakout: that smaller, sharper movement can be more effective than big, sweeping break and prioritizing spin rates.