11 underrated relief pitchers who will become household names in the MLB Postseason

Around all corners of the baseball world, relief pitchers normally don’t see the publicity starters and star position players receive. Emmanuel Clase, Mason Miller, Edwin Diaz, Josh Hader, and Devin Williams have been some exemplary exceptions to that rule. Outside this select group, only trade candidates and free agent relievers normally get their share of the press.

Today, we’ll take some time to highlight a few names that aren’t well recognized outside of their fanbases but will be after they excel under the bright lights of the 2024 postseason. How are we supposed to determine which pitchers will excel in the postseason? These are the relievers that have pitched to sub-2.00 ERAs and have labored for over 40 innings of work this season proving they can keep it together over the long stretch. In other words, it’s an educated guess. But these relievers are the most likely amongst bullpen pieces to have a golden moment in the limelight. Let’s give them a look.

(All pitch speeds and advanced data/metrics gathered from Baseball Savant)

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11. RHP Griffin Jax, Twins

Griffin Jax, son of former NFL player Garth Jax, is laying the foundation of a great career from the Minnesota Twins’ bullpen this year.

This is Jax’s fourth year in the MLB. After scuffling in his debut year, Jax started putting the pieces together and posted two years of sub-4.00 ERA pitching. But this year, he is pitching to a phenomenal 1.86 ERA through 53.1 innings and is quickly becoming one of the top relievers in the game. He has collected 69 strikeouts in that time and held opponents to a .180 batting average. Both his changeup and sweeper create high levels of whiff and chase. He mixes them well with a four-seamer that averages 97 MPH. If he can maintain this excellence for a few years, it will be hard for his achievements to go unnoticed.

The Twins are currently three games back in the AL Central and are holding onto the second Wild Card spot. Even with the Wild Card spots being hotly contested, Minnesota will most likely find themselves in the postseason. The problem will be making a deep run. The Twins have not seen an ALCS since 2002, though they have made it to nine postseasons since then. Nonetheless, we will almost certainly be seeing Jax pitch in October, especially if the Twins can advance.

10. RHP Tayler Scott, Astros

When we hear the words "Houston Astros" and "bullpen," we immediately think Josh Hader, Ryan Pressly, and Bryan Abreu. But there has been one arm that has outshined all three of Houston’s most reliable bullpen studs by a wide margin. That would be Tayler Scott.

Since debuting in 2019, Scott bounced around through the hands of seven teams, missed all of 2020 and 2021, and performed quite poorly until now. This season, Scott has flipped the script, throwing 56.2 innings to the tune of a 1.75 ERA. His 59 strikeouts doesn’t make him a master strikeout artist, but his .161 opponent batting averae has been spectacular. His four-seamer isn’t overpowering averaging at 92.6 MPH (his sinker averages at the exact same velocity), but his four-pitch arsenal is responsible for a decent groundout to air out ratio of 0.93. In any case, fly out or ground out, Scott keeps runs off the board.

After early struggles, the Astros have taken the top spot in the AL West staving off the Seattle Mariners by 3.5 games. The Astros have sustained several injuries to key pieces of their pitching staff this season accounting for their struggles, but they have proven they are still a dangerous team with their surge to the top. As dominant as the Astros typically are, we will likely be seeing a lot of Tayler Scott come October.  

9. LHP Tanner Scott, Padres

This brings us to one of two San Diego Padres bullpen weapons. Tanner Scott (not to be confused with the name above him) is one of the few names on this list who made the news this season. If it weren’t for all the swirling trade rumors and the eventual trade from the Miami Marlins, most baseball fans likely wouldn’t have had the chance to notice how good this guy really is.

Scott has been a feast or famine pitcher since being called up in 2017. All his season ERA stats are either above 4.00 or below 3.00. This year, it is below 2.00. The soon-to-be free agent has thrown 52.1 innings with an amazing 1.38 ERA. In addition, he has logged 62 Ks and held hitters to a minute .142 batting average. Scott maintains an astounding 1.21 groundout to air out ratio proving he is a groundball pitcher when he's not collecting strikeouts. Scott's four-seamer averages 97 mph, but the star of his two-pitch mix has been his slider which gets most of the whiff.

The Padres have surged recently and have taken the second Wild Card spot by storm. They sit three games behind the Dodgers, just above the Diamondbacks, for control of the NL West. Now boasting one of, if not, the best bullpen in the NL, the Padres seem primed for a postseason run. We can expect to see Scott this October.

8. RHP Robert Suarez, Padres

Robert Suarez is our second Padre reliever that is sure to leave an indelible impression this October. Suarez came up in 2022 and delivered a great performance. Last year, a stint on the injured list, plus a 10-game suspension for sticky stuff prevented him from pitching most of the year. But this season, he is better than in his debut year. Suarez has thrown to a 1.68 ERA through 48.1 innings. He has accumulated 49 strikeouts and held opponents to a .194 average.

Suarez boasts a high-octane fastball averaging 98.9 mph which is somewhat perplexing as he does not record strikeouts at a very high rate. His sinker isn’t far behind at 98.6 mph. With his two high-speed options being his main weapons, hitters are usually thrown off balance when he flashes his lesser-thrown changeup which accounts for a high rate of whiff. Even with using his high-speed offerings the most, he usually sees a lot of weak contact from hitters.

With Suarez, Tanner Scott, and Jason Adam headlining the Padres bullpen, San Diego is in win-now mode and will look to push for a World Series trophy this season.

7. LHP Bryan Hudson, Brewers

While Devin Williams was on IL, the Milwaukee Brewers were forced to stretch their bullpen. Luckily, Bryan Hudson stepped up and performed admirably.

Hudson came up last year and pitched 8.2 innings to disastrous results. But this year, the rookie has truly broken out pitching to a 1.68 ERA over 53.2 innings. Hudson has recorded 56 strikeouts and held opponents to a meager .144 average. His four-seamer isn’t very flashy sitting at 91.6 mph, but it has an excellent run value. The three-pitch mix he employs doesn’t get a whole lot of whiff or chase yet he throws on average 4.05 pitches per plate appearance which is extremely effective.  

The Brewers currently hold the top spot in the NL Central with seemingly no competition. But with the loss of Christian Yelich, Milwaukee’s postseason might be a short one. The Brewers have not been to a World Series since 1982 when they lost to the St Louis Cardinals as members of the AL East. The Brewers have never won a World Series since their founding in 1969 as Seattle Pilots. Still, we should see the full extent of the Brewers deep bullpen in action as they fight for survival against the titans of the NL.

6. RHP Hunter Gaddis, Guardians

When we look at the Cleveland Guardians’ relief corps, we see excellence up and down their bullpen. No reliever has been better this year than Emmanuel Clase who maintains an 0.64 ERA. But beyond him, there are a few newer names that deserve some recognition. At the forefront, there is Hunter Gaddis.

Gaddis came up in 2022 but still qualifies as a rookie. Last year didn’t go very well for him as he posted a 4.50 ERA, but he has since become one of the best relievers in the game. Gaddis has pitched to a 1.43 ERA through 56.2 innings this season. He has less strikeouts than innings pitched with 53, but he has held opponents to a .159 average. Gaddis has a very low groundout rate but doesn't allow many hard-hit balls. Gaddis' four-seamer averages 95.4 mph and offsets it with two offerings ranging from the low to high 80's.

Cleveland currently sits on top of the AL Central and once held the best record in baseball. The Guardians’ main strength all year has been their excellent bullpen. If it comes down to the bullpen, the Guardians will be in very good shape and may go far into October. In the end, Clase might steal the show, but if Gaddis pitches to the same results he currently maintains, he will likely start getting the respect he deserves.

5. RHP Jeff Hoffman, Phillies

Jeff Hoffman made his debut in 2016 and had a very rough time getting outs until last year when he put together his first great season. Hoffman posted a 2.41 ERA in 2023, the first time he finished a season with a sub-3.00 ERA. Now, he seems to be building on his newfound success with the Philadelphia Phillies.

Hoffman maintains a 1.92 ERA through 51.2 innings. Over that span, he has accumulated a remarkable 73 strikeouts while holding opponents to a .196 average. Hoffman has certainly grown into a strikeout pitcher, something he wasn’t in prior seasons. He throws a four-seamer that averages 96.6 mph, his most successful pitch. His four-pitch mix results a low hard-hit rate with plenty of whiff and chase.

After some initial struggles racing against the Braves, the Phillies are now running away with the NL East. For the past two years, the Phillies have made deep postseason runs. In 2022, they lost to the Astros in the World Series. In 2023, the lost to the Diamondbacks in the NLCS. With an improved team this year, we can expect the Phillies to be a formidable competitor. It is very likely we will get many opportunities to see Hoffman at work.

4. LHP Alex Vesia, Dodgers

As a member of the Los Angeles Dodgers, Alex Vesia has already seen his fair share of press. The Dodgers are annual contenders and Vesia has been a big part of that since 2021. Still, Vesia hasn’t pitched more than nine postseason innings. That may soon change.

Vesia made his debut with the Marlins in 2020 before being traded to the Dodgers. This year, he owns a 1.75 ERA through 51.1 innings holding opponents to a measly .160 ERA and collecting 69 strikeouts. Vesia doesn’t boast an overpowering four-seamer sitting at 93.4 mph and his three-pitch mix doesn’t produce a whole lot of chase or grounders. However, he does generate a lot of swings and misses. Hitters have a very tough time trying to barrel his offerings making him extremely effective.  

The Dodgers hold a 3.5 game lead over the surging Padres in the race for the NL West crown. With Betts back as well as the addition of Flaherty, we can expect that lead to widen. The Dodgers will no doubt be entering the postseason as a heavyweight. With few other reliable relievers on the Dodgers’ pitching staff, we will surely be seeing Vesia at crucial moments for Los Angeles. 

3. RHP Justin Martinez, Diamondbacks

The Arizona Diamondbacks' rookie sensation, Justin Martinez, made his debut last year. While his career started on a rocky note, this year has been great for Martinez who maintains a 1.87 ERA through 53 innings. He has thus far logged 64 strikeouts with a .201 opponent batting average. With a groundout-to-air out ratio of 2.30, Martinez has established himself as, not only a strikeout pitcher but as the top groundout pitcher in the game. Martinez’s four-seamer and sinker are explosive, averaging 100.1 mph. He generates a ton of whiff while giving up few walks. With all the injuries to the Diamondbacks’ pitching staff and the fact that they had few reliable relievers before the trade deadline, Martinez certainly deserves his fair share of credit for his team’s success.

The Diamondbacks are just behind the Padres sitting 3.5 games behind the first-place Dodgers for the lead in the heated race for the National League West. They currently hold the first NL Wild Card spot. The Diamondbacks once more have a lane to shock the world and wind up in the World Series for two consecutive years. If that happens, we will likely be seeing a lot of Justin Martinez.

2. RHP Raisel Iglesias, Braves

This brings us to our first of two Atlanta Braves’ pitchers. In his 10-year career, Raisel Iglesias has finished seven years with an ERA below 3.00. He is truly one of this generation’s great relievers. This year, he is exceeding even those high expectations. Iglesias maintains a 1.54 ERA through 46.2 innings. He has also logged 45 strikeouts while holding opponents to a .145 batting average. The low strikeout total is uncharacteristic of Iglesias, but his results have never been better. Iglesias sports a four-seamer that averages 95.3 mph, while his sinker sits at 95.4 mph. His four-pitch has generated plenty of chase and whiff this season though his strikeout numbers are down. The bulk of that has come from his slider which perfectly offsets his usual high-speed offerings.

The once mighty Braves are now holding tightly to the third NL Wild Card spot. They are half a game up on the New York Mets and four games behind the Diamondbacks for the second NL Wild Card spot. The NL East is now securely out of their hands. Should they hold on, Atlanta will bring one of the NL’s best bullpens into the postseason. We’ll undoubtedly see Iglesias in to close it out or keep the Braves in games when going through tight spots.  

1. LHP Dylan Lee, Braves

Our second Braves’ reliever hasn’t garnered the reputation for quality that Iglesias spent years compiling, but he is well on his way. Dylan Lee made his debut in 2021 but only pitched two innings that year. We witnessed a flash of brilliance the next year when he threw to a 2.13 ERA, but 2023 went very poorly for him. He was also sidelined for most of the year with a shoulder injury that required surgery. Now, he is healthy and back on track. Lee currently owns a 1.91 ERA through 47 innings. He has accumulated 52 Ks on the year and has kept hitters to a .225 average.

Dylan Lee doesn't throw a high-velocity fastball with a four-seamer that averages 92.1 MPH, his least successful pitch with an opponent batting average of .321. However, his three-pitch mix generates a ton of chase and whiff. In addition to the strikeouts, Lee also gets plenty of groundballs. With great results in the past, we can only assume he is getting better. Lee has been an indispensable reliever for the Braves this year and he will certainly be a key bullpen piece should they make it to the postseason.

Honorable mentions: Jared Koenig (Brewers), Jason Adam (Padres), Cade Smith (Guardians), Tim Herrin (Guardians), Jorge Alcala (Twins), Matt Strahm (Phillies), Carlos Estevez (Phillies), Ryan Thompson (Diamondbacks)