What will the bullpen look like in 2025?
Two seasons ago, the Kansas City Royals had one of the worst bullpens in franchise history. Not looking to repeat that, the front office made it a point to improve the relief pitching that offseason. They signed free agents and made trades to that end. Not every move they made worked out, but the bullpen was considerably better in 2024. The Royals haven’t made any notable additions to the unit this offseason, but they have many more options to fill out the group than they did a year ago. Let’s take a look at who the candidates are to start the season in Kansas City’s bullpen.
The man: Lucas Erceg
After arriving in a deadline trade with Oakland, Erceg flat-out dominated last season in blue. He had a 2.88 ERA in 25 innings after joining the Royals with a 1.17 FIP. He led all relievers over the last two months of the season in fWAR. He was having a solid season for the A’s but was on another level after the trade. After posting a 14.3% walk rate in 2023, he cut that to 8.3% at the time of the trade. He further slashed that to 3.1% after arriving in Kansas City. I have concerns about how sustainable that improvement is given his overall zone rate only marginally increased. Erceg has room for regression though — he could still be a highly effective late-inning reliever even with a 9% walk rate. This is arguably the best relief arm the Royals have had since Wade Davis was at his peak.
The locks: Hunter Harvey, John Schreiber, Chris Stratton
All three of these guys will almost certainly begin the season on the 26-man roster due to some combination of their performance and their contract status.
Harvey only managed 5.2 innings for the Royals before going down with injury, but he had a 3.17 FIP for Washington before being traded and had been very good across the prior two seasons. He should regularly pitch late in games. Harvey will reach free agency after this season so he could be a trade piece should things go sideways for the Royals in the first half.
Despite his strikeout rate cratering relative to his three previous seasons, Schreiber was one of the more reliable bullpen arms in Kansas City last season. He kept the ball on the ground and allowed just one homer all season. He’s not an ideal fit for high leverage due to his platoon splits — lefties hit .276/.347/.414 against him in 2024 compared to .216/.302/.243 for right-handed batters — but his groundball tendencies make him a useful fireman.
Stratton had a rough go of it in 2024, posting a 5.55 ERA with a career-high 12.8% walk rate and his worst strikeout rate since his abbreviated rookie campaign way back in 2016. His velo and spin rates were both down and hitters were more patient than ever when facing him, swinging at a career-low 42.9% of his pitches. There are numerous red flags in the 34-year-old’s statistical profile, but he’s under contract for just $4.5 million and had a 3.51 FIP from 2020-23. Stratton will get opportunities in low and medium leverage to see if he can bounce back, but the Royals should be willing to cut bait if he hasn’t sorted himself out by the summer.
The probable returners: Sam Long, Angel Zerpa
Both of these lefties are coming off career seasons out of the pen and should have a role to start 2025.
Long joined the big league staff in late May and didn’t allow an earned run until his twelfth appearance, finishing the season with a 3.16 ERA. The metrics under the hood paint the picture of a serviceable middle reliever who compensates for a lackluster fastball by throwing lots of breaking balls. The 2025 season is an important one for Long. He’ll turn 30 in July and is out of minor league options, so this is the year to prove that he belongs in the big league bullpen.
Zerpa tossed a career-high 53.2 innings in the majors in 2024 despite being demoted to Triple-A at the end of a rough August. He was recalled in September and didn’t allow a run across seven appearances to close out the season. He didn’t miss many bats, but he posted a 59.2% groundball rate thanks to ramping up his sinker usage. His low slot makes him a difficult matchup for lefties but gives right-handed batters a good look. Zerpa has one option year remaining, so he doesn’t need to stick on the 26-man roster all season. He’s a situational lefty arm that could become very familiar with I-29 this summer.
The potential starters: Daniel Lynch IV, Kris Bubic, Michael Lorenzen, Alec Marsh, Kyle Wright
The starting rotation will almost certainly open the season with Cole Ragans, Seth Lugo, and Michael Wacha in some order. That leaves five other potential starters competing for the remaining two or three spots.
Lynch has pitched in parts of four seasons in the majors now and has not lived up to the potential he demonstrated in the minors as a starting pitching prospect. However, he may have turned the corner pitching out of the bullpen. In 20.2 innings across 11 appearances after being recalled in late August, he did not surrender an earned run, allowing just 15 baserunners while striking out 24. Lynch pared back his fastball usage in relief, leaning more on his slider and changeup. Hopefully, his improved performance proves sustainable, but he still has an option year remaining should it be needed.
After rehabbing from Tommy John surgery, Bubic returned to the big league club in early July and quickly established himself as one of the team’s best relief arms. He posted a 2.67 ERA in single-inning relief with elite peripherals. He made several adjustments in his first action in over a year. Bubic ditched his curveball in 2024, favoring instead a slider that he had soft-launched in 2023. He also altered his fastball shape, getting more vertical ride and a bit less arm-side run than he had previously. This proved to be a more effective shape, helping the offering punch above its weight despite sitting at 93 mph, below average velo for a reliever.
It will be fascinating to see how the Royals deploy him — do you try a return to the rotation, or do you just let him eat in the late innings? He totaled 66 innings last year between the minors and MLB, how big of an increase in workload could he handle? Whether in the rotation or bullpen, Bubic should play an important role on Kansas City’s pitching staff in 2025.
Lorenzen spent the first half of 2024 outperforming his FIP in Texas’s rotation before doing the same in his brief Royals tenure following the trade deadline. There are many reasons to believe he won’t be so fortunate in 2025, such as his .213 BABIP against and 89.0% strand rate in a Royals uniform. However, he made adjustments like ramping up his sweeper usage in Kansas City.
He also has a deep arsenal of pitches that play well off of each other — new research from Baseball Prospectus had Lorenzen as the most difficult starter in MLB last year for batters to identify what pitch was coming. His command is better than his walk totals indicate. He should start the season in the rotation as his arsenal depth makes him less susceptible to the times through the order penalty. If he struggles, it would be interesting to see how his kitchen sink approach plays in relief.
Marsh was a perfectly cromulent back-of-the-rotation starter in 2024, posting a 4.53 ERA with similar peripherals in 129 innings. He was much better from a strike-throwing standpoint but was unable to maintain the high strikeout rates he consistently posted in the minors. He threw six different pitches with good stuff, but Marsh didn’t command his breaking balls well and they were hit hard as a result. He should continue getting opportunities as a starter but maybe letting him air it out in the bullpen would bring back the whiffs.
Wright is perhaps the biggest wild card on the staff. In his only full, healthy season in the majors, he posted a 3.19 ERA in 180.1 innings. That was back in 2022. The next season, he hit the IL three separate times due to right shoulder issues and, after the season, underwent surgery on it that would keep him out for all of 2024. The Royals traded for him after the surgery, hoping he could contribute in 2025 despite a limited sample of pitchers successfully recovering from such a procedure.
He will presumably work on some sort of innings limit this season and pitching out of the bullpen would be a natural way to limit workload, but Wright has been almost exclusively a starting pitcher in his pro career. He has an option year remaining so he’ll likely start the season building up in Omaha’s rotation, but it wouldn’t be surprising to see Kansas City opt to pitch him out of the bullpen instead.
The minor leaguers: Carlos Hernández, James McArthur, Steven Cruz, Evan Sisk, Eric Cerantola
These are guys that either spent 2024 in the minors or pitched in the majors and were left off the postseason roster. Any of these guys would have to earn a major league roster spot in Spring Training or show enough in the minors to warrant promotion.
This upcoming season is a make-or-break season for Hernández. He frequently shuttled between Triple-A and the majors last season but was pretty good for the Royals, posting a 3.30 ERA in 30 innings, most of which were low leverage. His strikeout and walk rates were pedestrian though, and he will almost certainly give up more than one homer this season considering he ran a flyball rate north of 50% last year. Crucially, he is out of options, so he’ll need to prove that he belongs on a big-league staff this season. If he pitches like he did in 2023, he’ll likely be DFA’d.
McArthur showed promise in a small sample in 2023 and entered 2024 as Kansas City’s closer. He quickly pitched his way out of that role, allowing runs in each of his first three outings and surrendering four homers in a ten-day stretch in May. By win probability added, he was the worst Royals reliever to throw at least ten innings. There are things to like in his profile. He gets grounders, throws plenty of strikes, and has two good breaking balls. On the other hand, his fastball is not very good, and he doesn’t command his breaking balls very well, too often finishing them over the middle of the plate. McArthur has an option remaining, so he’ll need to really impress in the spring to start the season with the major league club.
Cruz spent most of 2024 in Omaha but got 5.2 innings in the majors toward the end of the season. He was solid in Triple-A and posted a career-low walk rate, but his strikeouts also dipped. Cruz has a 70-grade fastball but little else, showing scattershot command and lacking a good secondary offering. He’s minor league depth with a good shot to pitch in the majors at some point in 2025.
Sisk and Cerantola both spent the entire 2024 season in the minors, finishing the year at Omaha. Sisk put together an outstanding season for the Stormchasers, throwing 57.1 innings with a 1.57 ERA and strong peripherals. Yet he never got the call, even when Kansas City’s bullpen was struggling midseason. Part of this is due to his below-average command. He’s also a low-slot lefty who lacks a pitch to attack right-handed batters. He should get a shot as a lefty specialist at some point, but there are at least three lefties ahead of Sisk on the depth chart. Cerantola started the season in a swingman role but by mid-June was being used almost exclusively in single-inning relief. He missed lots of bats in that role but also allowed four homers in 26.2 innings. His walks were still elevated but were at a more acceptable level than when he was pitching multiple innings. Cerantola will likely join Sisk waiting for the call in Triple-A.
The non-roster invitees: Taylor Clarke, Austin Cox, Junior Fernández, Beck Way, Anthony Simonelli
These are guys that pitched in a bullpen somewhere last year that have received invitations to spring training.
Clarke signed a minor league deal last offseason with the Brewers and spent the entire season pitching for Triple-A Nashville, mostly as a starter. He never got the call and will now enter spring training looking to win a spot in Kansas City’s bullpen. He struggled with the long ball in his last big league action, surrendering 12 homers in 59 innings in 2023. Cox signed his third minor league deal in the past 14 months with the Royals a few weeks ago. He was serviceable in a multi-inning role for the team in 2023 but spent all of last season in the minors. His strikeouts ticked up, but he also walked the farm. He could be an option for a low-leverage, multi-inning relief gig.
Fernández has pitched 54 innings in the majors across parts of four seasons, the last of which was 2022. He spent 2023 in Triple-A and last season in Japan, where injuries limited him to just two appearances. He throws gas but has regularly struggled with walks and got hit hard in his last go at affiliated ball. Way’s development has stalled out in two and a half seasons in the org. The Royals pulled the plug on him as a starter in 2024, but he was as wild as ever in a single-inning role. The stuff is still intriguing and he’s only 25, but he likely won’t be more than an up-and-down guy given his lack of command. Simonelli dominated Double-A in 2024, struggled upon promotion to Triple-A, then cooked in the Arizona Fall League. He’s been the most successful pitcher in this group over the past two seasons.
How would you line up the Royals bullpen to start the season?