Going into the 2020 season, I spent a lot of time and a number of articles focusing heavily on the Baltimore Orioles bullpen, expecting the group to be not just a viable unit on a bad team, but a legitimate unit that was going to stand out.

And stand out they did.

(You can discuss this on the BSL Board here.)

It’s time for part two of our Orioles 2021 outlook series, focusing on the top storylines to follow out of the Orioles bullpen, the red flags to pay attention to, and which rookies we can expect to see at some point in 2021 and what they will bring to the roster. For part one of this series that focused on the starting rotation, you can check that out here.

The Orioles finished 2020 tied with the Oakland A’s for the fifth-highest bullpen Wins Above Replacement (3.0), a massive upgrade from the 28th-ranked 0.4 fWAR in 2019. You can clearly see the progression in a number of important areas below.


There’s still plenty of room for growth with this unit, but when talking about a very young team that’s still in the process of acquiring talent and putting themselves in a position to contend, with roster turnover constantly shaking things up, it’s important to note these improvements, led largely by a small group of young arms.

To note, the 0.93 HR/9 rate was the fourth-lowest mark in baseball last season, their ground ball rate ranked fifth, and the 36 point drop in wOBA was tied for the highest improvement among all major league bullpens in 2020.

We also can’t forget what Mychal Givens and Miguel Castro brought to this team. The Orioles acquired three new Top 30 prospects and two young international prospects for a decent middle-relief arm in Givens and an uber-talented arm in Castro, who hasn’t been able to put it all together despite six seasons in the big leagues (Mets fans have already fallen into the same trap we did when it comes to Castro’s potential).

But can we expect to see continued growth in 2021, a season likely to feature a full 162 game schedule and a young Orioles rotation that will surely experience growing pains and a few potential long nights for the bullpen? With the current talent that resides in the bullpen, combined with the young pieces expected to break through, the Orioles bullpen should be a bright spot once again in 2021.

RHP Hunter Harvey

There’s no particular order here when breaking down each bullpen arm, but let’s dive in with RHP Hunter Harvey, who is entering his age-26 season, but feels like he should be 36 at this point. Six years after the Orioles used a first-round draft pick on Harvey, the North Carolina native finally made his MLB debut in 2019, showcasing an electric fastball and giving fans hope that he could emerge as a reliable late-inning arm in 2020. Unfortunately, the injury bug returned and Harvey’s 2020 season was pretty bad.

Harvey tossed just 8.2 innings, posting a 4.15 ERA (5.22 xERA), giving up eight hits and two walks with just six strikeouts. He was worth -0.1 fWAR. We’re talking about a very limited number of innings, having logged 15 innings at the major league level over the past two seasons, so it’s not time to jump ship when it comes to Hunter Harvey, but his window to prove he can stay healthy and be productive across a full season seems to be closing fairly soon.

Harvey lost a tick on his fastball last season, averaging 97.3 mph after averaging 98.3 mph in 2019, and he really struggled to produce swings and misses with his typically effective curveball, but he’s been on top prospect lists every year since 2013 for a reason. With a large group of both relief prospects and starting pitching prospects who project as possible bullpen pieces quickly approaching the gates of Camden Yards, Harvey will need to finally prove himself this season, or risk being pushed out of the mix.

RHP Shawn Armstrong

Since joining the Orioles via waiver claim from Seattle in 2019, Shawn Armstrong has been an underrated piece of Baltimore’s pitching staff that deserves a bit more love. Armstrong was worth 0.7 fWAR in 2019 after joining the Orioles after being worth 0.0 fWAR across his first three seasons in the majors, but he still recorded a 5.13 ERA with a 10.5% walk rate across 54 innings.

Injuries limited him to 10 innings in 2020 where Armstrong posted a 1.80 ERA (2.99 FIP) and a 0.80 WHIP, while holding his strikeout rate steady at 25%, slashing his walk rate in half to 5.3%, and seeing a big jump in ground balls (30.4% > 43.6%). It’s harder to walk guys when you throw 72% of your first pitches for strikes, a 15% jump from 2019.

Clearly, Armstrong has made some adjustments to his game and they started to pay off last season before injuries largely derailed his season. The Orioles elected to tender him a contract earlier this winter, meaning he will ideally play a major role in the 2021 bullpen with his ability to work more than three outs in an outing. But don’t get too attached to Armstrong if he comes out of the gates hot this season.

We saw what Mike Elias was able to do with Givens and Castro at last year’s deadline and there’s a real possibility that Armstrong meets the same fate. The 30-year-old reliever is under a very cheap contract and if a team comes calling for a reliever at next year’s deadline, you move him.

RHP Cesar Valdez

Look, Cesar Valdez was one of the coolest stories of 2020, but he’s getting ready to turn 36 and he has just one pitch, albeit a fantastic pitch. Making nine appearances, Valdez recorded a 1.26 ERA with a 0.70 WHIP, and a .140 average against across 14.1 innings, striking out 12, walking three, and not allowing a single home run. Luckily for Valdez, his “deadfish” changeup isn’t a pitch that’s going to wear down his arm and he could theoretically be around for a few more seasons, but I’m very hesitant to believe he holds up across a full season. Whatever production he can give the Orioles in 2021 is a big plus.

Dillon Tate

One of the more underrated players on the Orioles active roster, Dillon Tate has found his home in the bullpen and is coming off a much improved 2020 campaign, despite two freak injuries (a comebacker to his forearm and a sprained finger after tripping in his apartment).

Across 12 outings, Tate recorded a 3.24 ERA with a 0.84 WHIP, a .158 average against, and continued to produce notable ground ball rates with a limited number of hard-hit balls. Only one baseball reached the stands against Tate last season in 16.2 innings as part of a bullpen that did a much better job of limiting home runs. According to Baseball Savant, Tate recorded a whiff rate north of 23% on all four of his offerings, including his slider which became a very effective pitch in 2020.

There is still a bit of caution when it comes to Tate. While he was able to produce more swings and misses across the board, Tate’s expected ERA of 4.71 was more than a full run higher than his ERA, he posted a dismal first-strike rate of 46.9%, and opponents were fairly patient with Tate, rarely chasing pitches outside the zone (which you don’t have to do if you’re consistently ahead in the count).

As a full-time member of the bullpen now, Tate has shown signs of becoming one of the more reliable pieces of this unit. Perhaps, we finally get to see some real value come out of the Zack Britton deal.

Tanner Scott

I think it’s safe to say that we finally saw the Tanner Scott fans have been waiting to see since the electric lefty brought his 100 mph fastball to the big leagues back in 2017. Scott made 25 appearances last season, recording a 1.31 ERA and a 1.06 WHIP. His strikeout numbers did take a slight dip to 26.7% but he improved in just about every other metric.

The 26-year-old ranked in the 93rd percentile while holding opponents to an average exit velocity of 85 mph on balls in play, mostly ground balls as Scott posted a career-high 58% ground ball rate. Combine that with his whiff rate which ranked in the 91st percentile and you saw very few hitters reach base, and many of those who did were wiped away with a double-play.

Scott’s biggest improvement came with his fastball. In 2019, Scott allowed a .505 wOBA and produced an 18% whiff rate with his 95.9 mph four-seamer. Those numbers looked quite different in 2020 as hitters recorded a .336 wOBA and whiffed 32% of the time against Scott’s fastball that reached 96.5 mph. His wipe out slider continued to live up to its reputation, holding hitters to a .079 batting average and putting up a 43% whiff rate. If he can replicate that sort of success with his fastball, 2021 will be another impressive season for Scott.

But keep an eye on that high walk rate. He still walked nearly 12% of hitters he faced and Scott’s xERA (3.62) and FIP (3.48) were both more than two full runs higher than his ERA. Like Armstrong and Tate, the expected numbers don’t quite match his standard numbers, which is something to keep an eye on.

Paul Fry

Fry very quietly had a solid season in 2020, seeing his strikeout rate jump from 21.6% to 29.6%, his walk rate fall from 11.4% to 9.2% and his ERA improve dramatically from 5.34 to 2.45 in his 22 outings. It was easy to point to Fry and say he would be greatly impacted by the three-batter minimum rule, but that wasn’t the case. In fact, the left-handed Fry was more dominant against righties, limiting RHH to a .227/.320/.318 slash, compared to a .273/.333/.477 slash against lefties. At 28, Fry is young enough to be a part of a winning Orioles bullpen, but if he pitches as well as he did last season and continues to show he can handle righties, they will surely be multiple suitors at next year’s trade deadline.

RHP Mac Sceroler/RHP Tyler Wells

We went into greater detail about both Sceroler and Wells on our latest episode of On The Verge which you can listen to here (do it!), but both Rule 5 picks will have a tough hill to climb if they want to make the active roster out of spring training. Sceroler pitched well in 117 innings of work back in 2019, posting a 3.32 FIP, 26.5% strikeout rate, and a 1.11 WHIP, but that success was at the High-A level. With a fastball that reach 95-96 mph in shorter stints, a big league curveball, and a decent changeup, Sceroler could find a home in the bullpen, but it won’t be easy.

It will be especially difficult for Wells to stick around, but there’s a lot to like. The 6’8” righty was a combined 10-6 with a 2.49 ERA, 0.96 WHIP, and .195 average against across 119 High-A/Double-A innings in 2018 before Tommy John surgery wiped out his 2019 season and 2020 was…2020. Some scouts see starter potential with Wells and he likely would have been in the majors in 2019 if it weren’t for surgery, but after not seeing game action since August 31, 2018 and a deep bullpen already in Baltimore, it wouldn’t be shocking to see him ultimately returned to Minnesota.

RHP Travis Lakins/ Cole Sulser

The duo of Lakins and Sulser are the wildcards in this bunch. Clearly, the Orioles are high on both pitchers, acquiring Sulser via waiver claim from Tampa Bay (who was also still semi-high on) and Lakins from the Chicago Cubs.

It was recently reported by MASN’s Roch Kubatko that Sulser pitched last season with a number of broken toes after an accident at home, which just might explain some of his disastrous numbers. Sulser was used as a multi-inning guy and then installed as the team’s closer, but struggled his way through a 5.56 ERA (4.91 FIP) and a 17% walk rate (19% K-rate) through 22.2 innings. Outside of his extreme walk rate, Sulser limited hitters to a .205 average and allowed just two home runs, so there’s good reason to believe that adjusting for broken toes may have broken the rest of his delivery and his command.

Sulser’s three-pitch mix was successful at limiting hard contact (84th percentile) and both his changeup and slider produced a whiff rate between 31-34%. I think he deserves a pass on 2020 and a hard look in 2021, as long as he doesn’t break any more toes.

As for Lakins, you really couldn’t have asked for much more out of a bullpen waiver claim during a pandemic. He led all Orioles relievers with 25.2 innings and recorded a 2.81 ERA while being a valuable multi-inning option out of the ‘pen (0.4 fWAR). Over his final six outings (all against AL East opponents, plus one outing against Atlanta), Lakins surrendered just one earned run on six hits with five walks and seven strikeouts.

It was those walks which proved to be an issue for Lakins throughout the season, issuing a free pass to 11.2% of hitters he faced. Combine that with a hard-hit rate approaching 45% and it would appear that Lakins was a bit lucky in 2020. A 4.01 FIP, 4.65 xFIP, and 5.32 xERA backup that claim. In fact, if you look at his Baseball Savant percentile ranking chart, you see that ranked among the bottom fifth of the league in most categories.

But, the Orioles will need bullpen arms who can go more than one inning and Lakins’ most used pitch, his cutter, was actually pretty effective (.239 wOBA, 24% whiff rate, one HR allowed). There’s going to be a lot of competition in camp, driving every arm to improve if they want to pitch at Camden Yards next season. With both Sulser and Lakins having minor league options available, they could end being valuable pieces on the Baltimore-Norfolk shuttle, which would be a noted upgrade over the typical options that have had express passes on this shuttle before.

Rookies to watch in 2021

Zach Pop may now be in Miami, but there are still a few impressive rookies down on the farm who will likely make an impact in 2021.

RHP Isaac Mattson (part of the Dylan Bundy return) spent last season in Bowie at the team’s alternate site, but surprisingly didn’t make his MLB debut in 2020. Mattson pitched at three different levels in 2019, even logging nine innings in Triple-A. Overall, Mattson struck out 110 hitters across 73 innings, posting a 1.01 WHIP and a .184 average against. With a fastball that reaches 95 mph, Mattson focused heavily on his secondary offerings in Bowie. He may begin the year in Norfolk, but if his slider and changeup show improvements in live-game action, he won’t be at Harbor Park long.

I also want to throw out two left-handed options who may get a look at some point. Tyler Erwin is a name the vast majority of Orioles fans haven’t heard of, but you should become familiar with him. His career really began to take off once he reached High-A in 2018, posting a 30% strikeout rate with a 1.00 WHIP and a 1.58 ERA across 68 innings in Frederick. He allowed just one home run in a very friendly ballpark.

That dominance continued in 2019 with Bowie. Erwin’s strikeouts dipped to 20%, but maintained good ground ball numbers, a 2.43 ERA, and he didn’t allow a single home run in 40.2 innings. In fact, the New Mexico State graduate has given up three home runs in 180 career minor league innings. That will do.

The other name is LHP Zach Muckenhirn. Another dominant bullpen arm on that 2019 Bowie roster, Muckenhirn finished with a 3.21 ERA (2.87 FIP)  and 65 strikeouts across 53 innings. He spent this winter in Puerto Rico, giving up one earned run across nine innings with 15 strikeouts and one walk.

He was at one point a Top 30 prospect and like I mentioned with Lakins and Sulser, having Erwin and Muckenhirn down in Triple-A as emergency options are a big upgrade over the likes of Jhan Marinez, Joely Rodriguez, and Andrew Faulkner (shoutout to anyone who remembers these arms and a free beer on me this year at Harbor Park).

It’s really difficult to trust a bullpen, but this unit took a big step forward in 2020 and is in a position to take another step forward in 2021. As long as the starting rotation can help them out by putting together longer outings, arms like Tate, Fry, and Scott will have the opportunity to shine. The ceiling is very high for the bullpen, but it’s a volatile group. Hang on tight, but trust the bullpen.

Nick Stevens
Nick Stevens

Orioles Analyst

A former high school teacher and coach in the mountains of Virginia, Nick Stevens has been writing about the Baltimore Orioles and their minor league system for five years. When he isn’t at a minor league stadium, he’s enjoying a Wizards game or supporting his alma mater, James Madison University. Co-Host of The Verge.