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As the baseball season is upon us, with Spring Training underway, the superstars of the MLB are returning and preparing for a full campaign after the 2020 abbreviated season. As everybody gets back into the baseball mood, let’s take a look at the 10 best relief pitchers, including both closers and middle-relievers, in MLB as 2021’s regular season approaches and consider who has a shot at being the best RP in 2021.
10. Aaron Bummer, White Sox
Starting the list off with a bang, Aaron Bummer of the Chicago White Sox is one of the best young relief pitchers in the league.
In his fourth season in the majors, he looked set to have his best so far, but it was cut short. He was only able to pitch 9.1 innings, due to some injury issues, but in that short period he was lights out. He had a ridiculous ERA of 0.96 and threw 14 strikeouts. This wasn’t a sudden fluke, though. He was great in 2019, too.
He pitched 67.2 innings, with ratios of 2.13 and a 0.990 WHIP. Bummer recorded 27 holds and 60 strikeouts.
Bummer will be in the setup role for a newly acquired teammate who we will talk about later and that can only help. The White Sox are going to be the real deal this year, and Bummer will be key in that.
9. James Karinchak, Indians
Another great young star, James Karinchak is one of the plethora of incredible pitchers from the 2020 Cleveland Indians. They had the best starting pitcher in baseball last year among one of the best rotations around, for a start.
They also had the leader in saves, who we’ll talk about later, and Karinchak was a standout rookie.
He pitched 27 innings with an ERA of 2.67 and an absolutely ridiculous 17.7 K/9. Yes, literally two strikeouts per inning. The 25-year-old will undoubtedly be a great pitcher for Cleveland for years to come, and starting off your career as the second-best rookie reliever in the league is an achievement that shouldn’t be undersold.
8. Edwin Diaz, Mets
Our first veteran is another player on a great team, as the New York Mets look to assert themselves as major contenders.
Their lineup is growing stronger by the year and their pitching staff has some great players. I recently crowned Jacob deGrom as the best starting pitcher in all of baseball and now we’re going to talk about his teammate.
Edwin Diaz is a closer who had a down year in 2019 but it is sandwiched between two fantastic campaigns which show his unbelievable potential. He only just turned 27 and if he can return to his 2018 form, when he had a 1.96 ERA, 0.791 WHIP and 57 saves, he will dominate with this new-look Mets team.
7. Drew Pomeranz, Padres
Another vet – and one who has been around the league with multiple different teams – Drew Pomeranz is poised for a great year.
He has never been a superstar huge name pitcher, but he is very solid. In 2020, he was more than just solid.
After a turbulent 2019 which started off poorly but ended very strong with a 25-game stint for the Brewers with an ERA of 2.39 and a WHIP of 0.911, he had his career-best year. The abbreviated campaign saw him throw 18.2 innings, for his new team, the Padres.
Pomeranz had an ERA of 1.45 and a WHIP of 1.018, throwing 29 strikeouts. The lefty is sticking around in San Diego and will be getting support from an absolutely stacked offense and a great rotation. He will also very likely be in a position to push for the league-lead in holds.
6. Aroldis Chapman, Yankees
We’re getting to the legitimately unhittable guys now. Aroldis Chapman has been one of the most dominant closers in Major League Baseball for years.
He made it to the majors with Cincinnati back in 2010 and has been throwing absolute fireballs ever since. Chapman is one of the most infamous power pitchers in baseball, throwing fastballs past hitters with ease. He has a career K/9 of 14.9 and has had multiple seasons of 15+. 100-strikeout, 30-save seasons are just another good year for Chapman.
Since joining the Yankees, he has not let up. Even at 33 years old he will still be up there in the discussion for the best RP in 2021.
5. Josh Hader, Brewers
One of the premier closing pitchers since he exploded onto the scene in 2017, Josh Hader is terrifying.
He is one of the most hard-to-hit pitchers out there and his career stats are unbelievable. Through four years – including a down year in 2020 – Hader has an ERA of 2.54, a WHIP of 0.858 and a K/9 of 15.3.
Those numbers are career-highs for most RP but that’s his average – and at 26 years old. His down year wasn’t bad by most standards, by the way, he still had a sub-1 WHIP and led the league in saves (13 in 15 opportunities).
The Brewers had a generally disappointing year but as they bounce back, their closer will too. Hader will be looking to continue to perform as one of the best relief pitchers in baseball.
4. Brad Hand, Nationals
A middle-reliever turned closer, Brad Hand has gone from a solid pitcher to a fantastic one since he switched role. After starting his career with the Marlins, it was the Padres who transitioned him to becoming a closer and he hasn’t looked back since.
From 2016 through 2020 he has an ERA of 2.70, a WHIP of 1.066 and a solid K/9 of 12.2. He led all of baseball in saves with the Indians last year and has now joined the Washington Nationals.
Leaving the stacked pitching staff in Cleveland would have been unfortunate if he wasn’t going to a team that has just as much star power on the mound. He will continue to be a great closer and one of the best relief pitchers out there.
3. Nick Anderson, Tampa Bay
Tampa Bay’s pitching staff is great and they get the most out of their players. Probably the best case of a star pitcher appearing out of nowhere is Nick Anderson.
After making the majors for the first time at 28-years old, in 2019 with the Marlins, you’d be forgiven for not expecting Anderson to be elite. However, after joining the Rays mid-season he started to heat up.
Then, in 2020 he showed up and he dominated. In his 23 games with Tampa in 2019, he got off to a good start with a 2.11 ERA, 0.656 WHIP and 41 strikeouts through just 21.1 innings.
Then he got even better. In the abbreviated 2020 season, he absolutely shredded batters, with absolutely unfathomable numbers. He had an ERA of 0.55 and a WHIP of 0.490, with 26 strikeouts in 16.1 innings.
Obviously, the sample size in 2020 is small, but you can only pitch the innings you get asked to pitch. Nick Anderson has been a revelation since joining the Tampa Bay Rays and with his ability to dominate in either the setup, high-leverage or closing roles, he will undoubtedly continue to feature as a star for the Rays. He might be older than most third-year players, but I think Anderson is going to be great for a while.
2. Devin Williams, Brewers
Earlier I alluded to a rookie who was somehow better than James Karinchak in 2020. Well, that would be Devin Williams.
Is it absurd that a Brewers pitcher is actually above Josh Hader on my list of best relief pitchers? Yes, it is. But absurd is a word that describes what Williams did in his opening campaign in Milwaukee.
He pitched 27 innings, which is more than most of the relievers on this list and his statistics were absolutely ridiculous. His ERA was 0.33, giving up literally 1 earned run on a homer in his 27 full innings. He had a WHIP of 0.630, with 9 walks and 8 hits total against him.
Batters facing Williams had a slash line of .090/.182/.157. He was unhittable.
Oh, and one more thing, he threw 53 strikeouts – that’s 17.7 K/9. Williams was an absolute superstar in 2020 and I can’t wait to see him pick up where he left off and try to maintain it. Last season, he won the rookie of the year, but honestly, he was also just straight up the best RP out there.
In 2021, I think he will naturally have some regression from the ridiculous numbers, but he will still be one of the best relief pitchers in the league.
1. Liam Hendriks, White Sox
The only person that I can rate above last year’s rookie superstar with a good conscience is star closer Liam Hendriks.
The 10-year veteran has been a good reliever for quite a while, but in the last two seasons he became a great one. The Athletics closer pitched 110.1 innings across that period and had an ERA of 1.79 and a WHIP of 0.897 with 13.1 K/9.
He recorded 39 saves in 47 save opportunities, which is fantastic. This offseason he joined the Chicago White Sox, one of the dark horse underrated teams who are pushing for a title. The White Sox already have some great pitchers, including Aaron Bummer, who opened up our list. They just added another one, with Liam Hendriks, who for my money is the best RP in 2021, until someone else can prove otherwise.
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