How does the Royals bullpen shake out post-Deadline?

With the trade deadline now behind us, the Kansas City Royals will look to re-hash their bullpen for the homestretch playoff run. The team is now 60-49, six games back from the first-place Cleveland Guardians. In the Wild Card race, the Royals hold a two-game lead over Boston for the third spot. The team’s bullpen was a clear focus at the trade deadline, and they made three moves that should impact just that. On the season, the team’s 4.27 reliever ERA ranks 22nd in baseball. That mark is the worst among current American League competitors. By strikeouts, the Royals’ relievers rank dead last in all of baseball with a 7.47 SO/9. Now post-deadline, how should the bullpen shake out?

Sifting through the Royals bullpen options down the stretch

High-leverage “closer” options

RHP Lucas Erceg

27.0% K% | 29.8% Whiff% | 56.1% FPS% | 12.8% SwgStr% | 18.9% K-BB%

Kansas City spent up to acquire Erceg from Oakland and it’s pretty clear why. Erceg comes in with a 98th percentile fastball velocity. He brings strikeout stuff to the bullpen that has been lacking it all season long. If there’s any real knock on him as a pitcher, it’s control of the strikezone. A converted infielder, Erceg offers the second-worst first-pitch strike rate of any arm in the new-look bullpen. That could limit him down the stretch, especially in high-leverage innings and postseason play. Regardless, as new as he is to pitching (he transitioned prior to 2022), you love the upside he offers. The Royals shouldn’t use him as a pure closer, but I don’t think they’ll use anyone as a pure closer. It should remain matchup-based, but Erceg is a lock for high-leverage innings moving forward.

RHP Hunter Harvey

25.7% K% | 27.7% Whiff% | 63.6% FPS% | 13.2% SwgStr% | 18.1% K-BB%

Harvey has a FIP of 5.07 since joining the Royals but that doesn’t concern me too much. Like Erceg, he brings great strikeout stuff. He’s also been great at limiting walks throughout his career. He offers 96th-percentile fastball velocity, but the rest of his pitch mix can be lacking at times. This is where I see Harvey and Erceg differ. Erceg has a very good breaking ball in his slider, and he does a great job limiting hard contact as a result. Harvey’s arsenal could be a bit more well-rounded, and he gives up a lot of hard contact. That could bite him and the Royals at times. Despite the shortcomings, I think he pairs very well with Erceg. If you need someone to strike guys out and prevent a home run, Erceg is your guy. If you need a guy to strike guys out without giving up walks, Harvey probably fits the bill more.

LHP Kris Bubic

33.3% K% | 34.7% Whiff% | 57.6% FPS% | 18.8% SwgStr% | 27.3% K-BB%

The Royals have been cautious with Bubic as he returns from Tommy John Surgery. I believe they’ll continue to do so, but he should be able to get consistent work in a SIRP role this season. In that role so far, he’s been the team’s best reliever by far. Bubic has posted asinine strikeout numbers and elite whiff rates. It’s only seven outings worth of work, so things could certainly regress some to the mean. Even if they do some, Bubic still belongs in this high-leverage role. He doesn’t blow you away with his pitch velocity, but spin rates and movement are next-level. Bubic may eventually become a starter again, but it wouldn’t hurt to see just how elite he can become as a back-end reliever.

Fireman – Put out fires and stop the bleeding

LHP Sam Long

28.7% K% | 29.4% Whiff% | 61.7% FPS% | 12.8% SwgStr% | 20.2% K-BB%

Sam Long may just be the best relief addition the team made this offseason. He was a non-roster invitee to spring training and has been dominant since being selected from Omaha on May 20. I’m not so sure the strikeout rate is sustainable for him long-term, and that’s the only reason I don’t see him as a true high-leverage option. Long’s fastball is below average, and that limits him some. However, it also makes him a good change of pace in relief of high-velocity starters like Cole Ragans and Alec Marsh. This season, he’s been a fly-ball pitcher who limits hard hits at a very good rate. That’s an excellent combination in Kauffman Stadium.

Lefty Specialist

LHP Angel Zerpa

21.4% K% | 14.7% Whiff% | 62.4% FPS% | 5.6% SwgStr% | 15.6% K-BB%

Zerpa’s numbers don’t look all that impressive on the surface. He struggles to earn punchouts and has some of the worst swinging strike rates on the entire roster. Against lefties, however, that’s not the case. Zerpa has a 27.8% strikeout rate against lefties this season. Against right-handed hitters, that mark is just 16.8%. His walk rate of 2.8% against LHH is five percent better as well. He’s a completely different pitcher against lefties and the Royals would do well to keep him in those situations as much as possible. He’s stranded 90.9% of baserunners when facing lefties, leaning on an extreme groundball rate. With Bobby and Maikel Garcia behind him, that’s a combination I like more often than not.

Leverage – Just not very high

RHP James McArthur

17.5% K% | 27.5% Whiff% | 66.1% FPS% | 12.6% SwgStr% | 13.1% K-BB%

I still believe McArthur will eventually find his way back to the upper echelon of relievers on this roster. His command is probably the best of any reliever on the Royals. He’s also actually induced more swinging strikes this season than last. Despite that, his strikeout rate has fallen eight percent compared to a year ago. The real issue is McArthur’s arsenal. Behind his fastball, nothing else has worked for him this season. His curveball and slider have both been scorched for a slugging percentage north of .500 this season. A year ago, opponents hit .194 and slugged .250 against the bender. Once McArthur can rediscover the feel for his curveball, he’ll once again have a put-away pitch to lean on and should be effective once again.

RHP John Schreiber

18.1% K% | 20.2% Whiff% | 53.0% FPS% | 7.9% SwgStr% | 10.2% K-BB%

Schreiber is currently on the injured list and it’s unclear just how long the Royals will be without him. He started his Royals tenure fairly strong, pitching to a 3.00 ERA through the month of May. Most of that was on the back of April when he finished the month with a 0.63 ERA. In May and June, his ERA finished above 6.00, and in July before the injury, he pitched to a 5.79 ERA. When Schreiber was at his best back in 2022, he leaned on an excellent fastball. Back then, the pitch offered an 87th percentile run value. He lived on weak contact and groundballs (58.1% GB%). He averaged 93.9mph on his fastball that season, but that mark is down to 92.3 in 2024. He’s maintained a high groundball rate but sits more middle of the pack with his fastball run value and hard-hit rates. He’ll need to re-discover his fastball to become the Schreiber of old.

Hybrid arms

RHP Alec Marsh

21.9% K% | 22.3% Whiff% | 60.0% FPS% | 9.2% SwgStr% | 14.4% K-BB%

Marsh really tapered off as the season progressed. He started very strongly as one of the better fifth-starters in the league. I think fatigue had a part in his recent struggles, and after the deadline, Kansas City has optioned him to Omaha in order to adjust his pitch load. They plan to taper him down to 30-60 pitches per outing, according to reports. I still think he could be a swing starter, and likely pitches behind an opener later this season in the big leagues. That’s similar to the role he had in 2023 when he pitched to a 3.77 FIP as a reliever. His stuff is good, and he has the potential to post solid whiff rates. It simply hasn’t happened consistently this season. With some rest and a lessened workload, I expect he could be more effective once again.

RHP Michael Lorenzen

17.9% K% | 21.7% Whiff% | 59.7% FPS% | 8.7% SwgStr% | 6.4% K-BB%

Lorenzen is a Kansas City Royal because he’s an experienced arm who will provide innings. I don’t think he’s going to provide innings in a Jordan Lyles type of way, but he also doesn’t exactly profile as an effective fifth-starter type. He simply doesn’t strike hitters out any longer. With a seven-pitch mix, Lorenzen gives the Royals a lot to work with. I think they can make some tweaks to help him re-discover more strikeout stuff. He’s never been an elite strikeout arm, but I think some tweaks such as mixing in his sweeper more often could help. His breaking stuff has been very ineffective this season and could be the key to helping him find better results over the rest of this season.

Mop-up – Just give us some innings to save some other arms

LHP Will Smith

14.1% K% | 23.2% Whiff% | 57.1% FPS% | 10.3% SwgStr% | 5.6% K-BB%

It’s been a train wreck for Smith this season. He doesn’t do many things well on the mound any longer, save for limited hard contact. His 5.51 SO/9 is the worst of his career. That’s on the back of a career-worst 10.3% swinging strike rate. His 57.1% first-pitch strike rate is the worst since 2020 when he posted a 7.38 FIP. It’s been difficult to rely on him for any important innings this season, and he’s best relegated to a mop-up role at this point. His veteran presence still matters some. However, I’m not sure he’s a lock to finish the season with the team. At one point, he was a lefty in a pen relatively void of lefty arms. Now, Bubic, Long, and Zerpa have solidified roles. That makes Smith more disposable than he once was.

RHP Chris Stratton

20.7% K% | 24.0% Whiff% | 59.8% FPS% | 9.1% SwgStr% | 6.0% K-BB%

Stratton, like Smith, seems to have finally met Father Time. Now in his age-33 season, Stratton has posted his worst strikeout totals since 2018. His command is the worst we’ve ever seen, evidenced by his career-worst 14.7% walk rate. He owns a player option for 2025, and at this point, it seems like he’d be ill-advised to decline that option. His career track record and those dollars owed probably save his spot in the organization until at least the middle of next season. He still does a great job limiting hard contact. He also has held opponents to a .199 average this season. The largest noticeable difference compared to a year ago is Stratton’s walk rate. As a veteran, I think the Royals can help him get that back and once he does, it’s easy to see how the results could be much better.