2024 in Review: Justin Slaten emerged in Boston’s times of despair as a promising bullpen savior

2024 in a single sentence

After serving because the sacrificial lamb in an early-season loss to the Mariners, Justin Slaten bounced again to place himself as a reduction ace following Kenley Jansen’s departure from Boston.

The Positives

Slaten’s rookie season was top-of-the-line seasons that we’ve seen from any Pink Sox reliever in latest reminiscence. Whereas the nearer duties had been largely left to the veteran Jansen, his late-season stint on the injured listing gave Slaten the prospect to fit proper into that nearer spot on the finish of the yr, which ought to transition properly into that function subsequent season, relying on Liam Hendricks’ standing and continued restoration over the offseason.

Slaten’s save in Boston’s final sport of the season was solely his second of the yr, however he picked up 13 holds and 6 wins in 55.1 innings out of the bullpen. Whereas all of those outcomes are nice, I feel an important numbers to showcase Slaten’s effectiveness aren’t within the sport outcomes he generated, however the person outcomes that his stuff generated in plate appearances.

He completed the yr with a 58:9 Okay:BB and within the 97th percentile for BB% and Chase%. Whereas his Whiff% completed at “solely” the 76th percentile, Slaten was capable of successfully generate mushy contact on these chases that didn’t find yourself being whiffs. His Savant profile was a factor of magnificence, as he completed above common in each single class and completed above the seventieth percentile in 12 of 13 statistics. I’m excited to see what Slaten can do after a full offseason of major-league work, and he’s an amazing bullpen piece to should return to a questionable group in 2025.

The Negatives

The one factor that Slaten should enhance on as his stuff is seen extra within the majors is his breaking ball… and the 4 blown saves. Slaten’s cutter and four-seamer carried out properly collectively (he ranked within the 88th percentile in fastball run worth), however his breaking ball mixture (a sweeper and rarely deployed curveball) didn’t hit the mark of a serious league high quality breaking ball duo.

He deployed the sweeper 24.7% of the time, his third-most used pitch, and allowed a .322 wOBA over the course of the yr. Opposing hitters hit .279 on the sweeper, which was his least constantly grouped pitch.

Slaten’s cutters and 4 seamers had been each grouped fairly tightly throughout their excessive utilization, however the sweeper was a bit in all places by way of induced break over the course of the yr.

Slaten additionally had some rocky moments in his take a look at drives within the nearer function, however I might be much less involved about that as he positive aspects extra expertise and is deployed in that function or an eighth-inning function extra constantly. Nonetheless, 4 blown saves in a restricted quantity of save probabilities.

Greatest Second

My favourite Slaten second of the yr needed to be when he secured his first profession save on Might thirty first after blowing a save simply a few months earlier than in his MLB debut.

Whereas that blown save in opposition to the Mariners actually wasn’t his fault (he was largely shoved right into a sport the place Boston ran out of relievers to face offense in a late-night West Coast sport for his first look as a Pink Sox), it was good to see him bounce again at a time when the Boston bullpen actually wanted his assist.

The Large Query

Can he repair his breaking balls to pair with the elevated heaters?

2025 and Past

Regardless of the place Slaten is slotted on this upcoming yr’s bullpen (depending on Hendricks and any offseason signings that will happen), his greatest focus this offseason must be on workshopping these breaking balls to be efficient and helpful in opposition to big-league hitting. One choice to do that could be both deploying his curveball extra (which was hardly ever used, however recorded his lowest batting common in opposition to on a single pitch when it was) or workshopping that sweeper to be extra managed. Each of those ought to up his already excessive chase charges, and if he’s capable of successfully pair them since they’re totally different sufficient, it might make his already threatening heater arsenal that a lot scarier with a reliable breaking ball duo.

Boston doesn’t have the most effective file relating to redeveloping breaking pitches over the offseason, however latest developments from the likes of Tanner Houck and Nick Pivetta give me hope {that a} important change might come for Slaten with this offseason’s work.