Who Are the Favorites for AL and NL Reliever of the Year?

Since 2014, Major League Baseball has presented the Mariano Rivera and the Trevor Hoffman Reliever of the Year Awards to the top relief pitchers in the AL and NL, respectively.

Previously, MLB handed out the DHL Delivery Man of the Year Award, but the honors have become far more meaningful now that they’re named for a pair of Hall of Famers instead of a shipping company. Who could have guessed?

Last season, the winners were Edwin Díaz in the NL and Emmanuel Clase in the AL, and there wasn’t much debate in either case. The same goes for the year before, when the winners were Josh Hader (NL) and Liam Hendriks (AL).

This year, however, the Reliever of the Year Awards could open up some fascinating conversations.

AL Reliever of the Year

In the AL, the question is whether Félix Bautista has played enough to take home the hardware. Through the first five months of the season, he was enjoying one of the most dominant relief performances in recent memory. He wasn’t just the best reliever in baseball; there were murmurs he deserved Cy Young support.

Unfortunately, a partially torn UCL potentially ended his regular season on August 25. Monday will mark a full month since he last pitched. While he still leads all relievers in FanGraphs WAR, he ranks 27th in the AL in innings pitched and 38th in appearances. It’s hard to know if voters will hold his absence against him.

For those who prioritize saves, Bautista is falling behind. The hulking righty trails AL leader Emmanuel Clase by nine saves and counting, and he ranks third overall in the AL. Among relievers with at least 25 chances, he ranks only fifth in save percentage. Jordan Romano of the Blue Jays leads him in both categories, and Ryan Pressly of the Astros has a chance to pass him, too.

Thankfully for Bautista, saves aren’t the only stat voters care about. The panel proved as much by selecting Devin Williams in 2020 after he spent the season as a set-up man for Josh Hader.

When Edwin Díaz won last year, he ranked fourth in the NL in saves and second in save percentage. More to the point, he had 32 saves in 62 innings pitched – that’s one fewer save and one more inning than Bautista.

If Díaz could win with 32 saves and 62 IP, Bautista should have this one in the bag. Among his peers (min. 60 IP), he ranks first in ERA, xERA, FIP, xFIP, and SIERA. No one else comes close to his 16.23 K/9, and he’s likely to finish with the AL lead in strikeouts (110).

Helping his case is the fact that there isn’t a clear second choice. Clase leads the league in saves (42) but also blown saves (11). Romano ranks second in Win Probability Added (WPA), but his 2.45 ERA is nearly a run higher than Bautista’s.

Chris Martin leads qualified relievers in ERA, but he only has 50.1 IP. Jhoan Duran went through a rough patch in August, while Aroldis Chapman has seen his numbers inflate over his last ten games.

Thus, with no direct competitor to steal the votes, Bautista remains the favorite. Here’s how the top contenders stack up:

The Favorite: Félix Bautista

NL Reliever of the Year

There’s no clear frontrunner in the NL race.

Alexis Díaz leads the league in saves, save percentage, and WPA. Tanner Scott leads in strikeouts and fWAR. Josh Hader ranks first in ERA and xERA among qualified arms.

Then there’s Devin Williams, who doesn’t lead in many categories but ranks among the top five in nearly everything. David Bednar is in a similar position.

The winner is almost sure to be one of these five names, but it’s hard to guess which one:

Díaz is the saves king, but his other numbers aren’t as impressive. Meanwhile, Hader and Williams have the edge in ERA, but the fewest innings pitched.

Scott deserves credit for the sheer volume of his workload, but the others have done far more work in the ninth inning or later.

Hader, for instance, has faced 199 batters in the ninth and given up only seven runs all year. However, despite closing out so many games, he hasn’t pitched nearly as many high-leverage innings as his competitors. While he has the most impressive numbers across the board, he still has the lowest WPA.

It’s not Hader’s fault that he hasn’t had as many high-leverage opportunities, but neither should Díaz be dinged for pitching in more difficult spots than anyone else.

Ultimately, this will come down to the voting panel’s priorities. If the voters like sheer dominance, Hader is their guy. If they want to reward durability and bulk, Scott has the edge. As for valiant effort in challenging spots, Díaz is a worthy choice. Finally, Williams and Bednar could represent a good compromise if the voters find themselves as torn as I am.

If I had to guess, I’d say Williams takes home the hardware, but really, there isn’t a wrong choice.

The Favorite: Devin Williams

Stats and rankings as of September 22.