Red Sox 2025 Season Preview: The Closers

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Who will Alex Cora give the ball to in the ninth inning?

Welcome to part three of my 2025 Red Sox pitching preview. We’ve already covered the starting rotation and the depth starters. Today we turn to the closers. Kenley Jansen is gone, so the ninth inning is up for grabs. At this point, it’s hard to say what direction Alex Cora will go. It could be one guy, or it could be closer by committee. Here’s a look at a few of the names that may be in the mix for the closer role.

Liam Hendriks

Let me preface this analysis by admitting I’m incredibly biased towards Hendriks. Regardless of his current baseball ability, he’s exactly who I want my closer to be. He’ll travel the country visiting children’s hospitals, taking photos, and being a charismatic Aussie during the day. The second he gets a baseball in his hand, though, he becomes an adrenaline-fueled lunatic, hurling profanities at anyone who dares to stand in the batter’s box. If I had one note for Hendriks, it’s that he needs a better entrance song than “We Will Rock You” by Queen. “Hells Bells” is spoken for, but pick something by AC/DC; they’re Australian. “Back in Black”, anyone?

Hendriks is your standard, no-frills closer. He throws a hard, flat fastball that averaged 97 MPH in his last full season. He also has elite extension, making the ball get on hitters even quicker. The flat attack angle of the pitch aids in missing bats, both in and out of the zone. The one knock on the pitch is that when it is hit, hitters have managed to do some damage. Outside of the fastball, Hendriks throws a slider and a curveball. Both breakers are thrown pretty much exclusively in the dirt, but hitters can’t resist. His fastball is good enough that hitters have to gear up for it, and that’s when Hendriks can pull the string and induce some truly terrible swings.

Hendriks hasn’t pitched in two seasons, though, due to cancer treatment and Tommy John surgery. Naturally, missing two seasons raises questions about Hendriks’ current ability. According to reports, Hendriks “hit 96 MPH” in one of his spring training outings thus far. That’s far off from averaging over 97 MPH, but the hope is that his velocity ticks up as we approach the season.

Garrett Whitlock

Garrett Whitlock is another name that’s been thrown in the closer conversation, mainly because he put himself in the mix, reminding Alex Cora that he closed the 2021 wild card game. Whitlock put himself on the radar as a reliever, anchoring the Red Sox 2021 bullpen. Nearly every time he stepped on the field, he was dominant. He attacked hitters in the zone with sinkers and finished them off with well-spotted sliders, changeups, and four-seamers. Just as importantly, he rarely ever walked hitters (5.7% walk rate).

Since then, he hasn’t been as dominant. His role has shuffled between the bullpen and rotation. He’s also battled injuries and made tweaks to his arsenal. As a reliever, Whitlock has historically used a more fastball-heavy approach.

I wouldn’t read too much into the 2024 numbers, as it was just four starts, and the Red Sox as a whole employed an off-speed first approach. Still, a return to the bullpen likely means Whitlock won’t have to go through a lineup more than once and can focus on attacking each batter rather than saving looks for later innings. On top of that, the bullpen also supplies a velocity bump. In 2021, his sinker averaged 95.9 MPH. With Whitlock’s elite extension, the perceived velocity was nearly 98 MPH. These factors combined to propel the sinker to a nearly 56% true first strike rate (The rate at which a pitcher gets to 0-1 with a pitch, 56% is an excellent mark). By getting ahead so frequently, Whitlock could then use his secondaries to put hitters away.

Those secondaries, despite Whitlock’s struggles as a starter, have been excellent. I’m mostly ignoring 2024 because Whitlock only made 4 starts, but looking back further, his slider and changeup have each generated whiffs at a strong rate. If Whitlock returns to the bullpen and can continue to attack hitters in the zone with his sinker, his slider and changeup are excellent options to end at-bats.

I think Whitlock is better suited for a multi-inning role because of his ability to mix pitches, but I see the appeal of using him in the ninth inning due to his strike-throwing. Whitlock has the stuff to excel in any role, so long as his body holds up. I think it’s unlikely Whitlock will become the de facto ninth inning pitcher and is rather used in high-leverage spots for multiple innings. No matter the case, a healthy Garrett Whitlock is a valuable weapon for Alex Cora to deploy.

Justin Slaten

Justin Slaten is the third name I would consider for the closer role, for similar reasons to the previous two: he throws strikes. Slate faced 119 right-handed hitters last season and issued just one walk. He’s also fairly platoon-neutral and can attack both sides of the plate, allowing him to enter the game without serious matchup concerns.

Against lefties, he used primarily a fastball and cutter. The fastball comes in close to 97 MPH with great extension, helping the ball jump on hitters. Lefties had a very hard time with the pitch, whiffing on 17% of fastballs. They also didn’t record a single “barrel”. Slaten’s cutter was okay against lefties as well. He was able to use the pitch to get lefties to expand the zone (40% chase rate) but also ran into issues when the ball sometimes found too much of the plate and was punished. He’ll also occasionally spike a two-strike curveball in the dirt, which has been effective as well.

Against righties, Slaten went with a cutter-heavy approach, and it was very effective. His cutter induced weak contact regularly (61% ground ball rate) and routinely earned strike one. His fastball wasn’t as difficult on righties with lower swinging strike numbers, but it still managed to create weak contact. He also has a sweeper that he uses to punch hitters out, picking up the slack for the fastball. Slaten does an excellent job spotting his breaking ball and glove side, causing hitters to chase at a high rate.

Much like Whitlock, his ability to generate whiffs and limit free passes makes him an intriguing option to close out games. He’s also not as matchup-dependent as other pitchers, making him a viable option in most games. He doesn’t have the same experience with the ninth inning as some of the other options, though, so I’d expect him to be further down the list of closers when the season begins.

Aroldis Chapman

I don’t have a ton to say about Aroldis Chapman that hasn’t already been said. I’m including him here because of his past closing experience. He’s a massive lefty with a rocket for an arm who has no idea where the ball is going on release. Most of his outings will likely be anxiety-inducing thanks to his lack of control, but he’ll strike a ton of hitters out, and we’ll get to point at the radar gun and laugh at the obserdity of it. Champan is equally tough on lefties and righties, so I don’t think he’ll be deployed solely against pockets of left-handed hitters, but I also don’t think he’ll be the primary ninth inning option with a healthy bullpen.

Fangraphs Projections

Around the Division

Yankees

The Yankees‘ bullpen is, unfortunately, going to be excellent once again. New York acquired Devin Williams from the Brewers. If I had to guess, he’ll be the primary closer, but the job could also go to Luke Weaver. Williams has experience with the eighth because he shared a bullpen with Josh Hader for a period, so he may be agreeable to either role. It’s worth noting that Williams is a frequent playoff choker and will likely choke again.

Orioles

Felix Bautista returns for Baltimore after missing a year with a UCL injury. The Orioles will be careful with him to begin the year, preventing him from going for multiple innings or pitching on back-to-back days. They also have some intriguing arms in their pen in Seranthony Dominguez, Yennier Cano, and Gregory Soto. Bautista is dominant when healthy, though, and has an elite closer entrance, so he’ll rightfully be given the ninth inning.

Blue Jays

The Blue Jays signed Jeff Hoffman this winter, presumably to be their closer. He was excellent in the two seasons he spent with Philadelphia but hasn’t ever been a full-time closer. He has three solid fastballs and will likely be fine in the role, but it’s something to monitor. After Hoffman, the Toronto bullpen isn’t overly scary. Yimi Garcia and Chad Green are solid but nothing to write home about, and Amir Garrett is a benches-clearing brawl waiting to happen.

Rays

Pete Fairbanks will likely be the “closer” for the Rays, but they’ll have a plethora of pitchers to hand the ball to in the ninth inning. Fairbanks is good, but he isn’t as sure a thing as Devin Williams or Felix Bautista. Edwin Uceta is another arm to watch. The Rays turned Uceta into an elite reliever thanks to his funky arm angle and flat fastball, and he could work his way into high-leverage situations. Drew Rasmussen is another excellent pitcher, but he’ll likely be stretched out to some degree.

If I had to rank the bullpens in the division, I’d reluctantly put the Yankees at number one. They have the arms to turn games into six-inning contests, and that’s a very dangerous thing. The Blue Jays are comfortably fifth, in my opinion. Hoffman is great, but outside of him, they feel incomplete. The middle three teams could be ranked in any order. If Liam Hendriks and Garrett Whitlock reach their potential after returning from injury, the Red Sox would be in the conversation for the best late-inning arms in the American League. If those two struggle, the unit could be an arm or two short. The Rays and Orioles are in similar spots where they’ll need a pitcher or two to step up to complete the bullpen, but they have solid options as it stands.

That completes my review of potential late-inning options for the Red Sox, but don’t worry, there’s plenty more pitching preview to come. Next up, I’ll be covering the lefties, and after that, the rest of the names I haven’t touched on. Don’t worry, your favorite non-roster invitee will be included.