Cooperstown Notebook: The 2023 Progress Report, Part IV

We began this series with Craig Kimbrel striking out José Ramírez to close out the All-Star Game, and I’ll admit, my original intent was to cover all of the pitchers in Part II. But as anyone who reads (or edits) my work knows, when it comes to the Hall of Fame and its candidates, I can go on, and on… and on. In part that’s because I like to use this series as an annual clearinghouse, covering the vast majority of the active players whom readers most frequently ask me about during the course of the year. It may not be a one-stop shop, but with the added volume comes some context for comparisons (Has Freddie Freeman caught up to Paul Goldschmidt? Who has a better shot, Carlos Correa or Francisco Lindor? And what about Trea Turner?) In part, it’s also because in the 20 years (!) since I introduced it, my JAWS system has become more complicated and more nuanced, requiring a bit of additional introduction. That’s particularly true when it comes to pitching, where during the 2022 election cycle, I formalized S-JAWS for starting pitchers and R-JAWS for relievers.

I had been messing with the latter since the 2019 cycle, in the context of Billy Wagner’s candidacy. The short version of the story is that while Baseball Reference’s flavor of WAR (which I use in JAWS) features an adjustment for leverage — the quantitatively greater impact on winning and losing that a reliever has at the end of the ballgame than a starter does earlier — to help account for the degree of difficulty, it’s not the only way to measure reliever value. Win Probability Added (WPA) is a context-sensitive measure that accounts for the incremental increase (or decrease) in the chances of winning produced in each plate appearance given the inning, score, and base-out situation. WPA can be additionally adjusted using a pitcher’s average leverage index (aLI) for a stat variably called situational wins or context-neutral wins (referred to as WPA/LI). Both of those are now in the sauce; R-JAWS is the average of a reliever’s WAR (including his time as a starter and a hitter, if any), his WPA, and his WPA/LI. The rankings, which I used to have to create by hand, are now on Baseball Reference, and Wagner, who ranks sixth and is the best reliever outside the Hall, is trending towards election after receiving 68.1% on the 2023 ballot, his eighth year of eligibility.

With Wagner likely (but not a lock) to gain entry and become the eighth reliever enshrined, the question of who could be number nine is an open one, particularly with Joe Nathan and Jonathan Papelbon failing to get 5% on the 2022 BBWAA ballot and Francisco Rodríguez polling at just 10.8% on the ’23 one (though Wagner spent his first three years in that vicinity). For awhile it appeared as though a trio of dominant closers was racing towards enshrinement, but inevitably, those final outs to nail down games became harder to come by.

With seven All-Star appearances, a 1.91 ERA, and 333 saves in his first nine seasons (2010-18), Kimbrel once appeared to be taking the fast track to Cooperstown. But since missing the first half of 2019 because a qualifying offer from the Red Sox crushed his market (his signing team would have lost a draft pick had he not waited until after the amateur draft), he’s been erratic. He posted a 6.00 ERA in 2019-20 with the Cubs, then was brilliant (0.49 ERA, 23 saves) for half a season before being traded across town to the White Sox, where he again put up an ERA north of 5.00 in a setup role. His 2022 season with the Dodgers — who let Kenley Jansen walk in free agency — was up and down to the point that he lost the ninth-inning job and was left off the postseason roster. But upon joining the Phillies as a free agent, the 35-year-old Kimbrel pitched his way onto the NL All-Star team this year, and has a 3.23 ERA, 3.31 FIP (0.08 higher than last year) and 15 saves in 15 chances thus far. On May 26, he notched his 400th save, becoming the eighth pitcher to reach that plateau.

So is Kimbrel back? His 38.6% strikeout rate and his batted ball stats (.159 xBA, .306 xSLG) suggest that’s the case. His fastball still averages a crisp 95.9 mph and his curveball remains lethal; batters are hitting .122 and slugging .234 against the latter offering, though his 38% whiff rate with the pitch is about 17 points below what it was from 2015-18. Of greater concern is that he’s become rather homer prone; this year’s 1.15 HR/9 marks his fourth straight year above 1.0. Still, with 409 saves, he’s only 15 from reaching fifth all-time, with the potential to surpass Jansen (411), Wagner (422) and John Franco (424) before season’s end. If he matches his ZiPS projection, he would climb from 13th to 10th in R-JAWS (note that because ZiPS doesn’t include WPA or WPA/LI, I’ve simply prorated these relievers’ current rates across their projected remaining innings). Another strong season could push him closer to — or perhaps past — Wagner’s 24.9 R-JAWS, which could solidify his case.

Jansen’s ups and downs in recent years have been less extreme than Kimbrel’s, but he’s changed addresses multiple times as well. After 12 seasons with the Dodgers (2010-21) that saw him evolve from a raw converted catcher to the cut fastball’s second-best practitioner (after Mariano Rivera), he spent a year with the Braves — the team he rooted for while growing up, as he followed fellow Curaçao native Andruw Jones — and notched an NL-high 41 saves before joining the Red Sox. Thus far, the 35-year-old righty has pitched pretty well, posting a 3.19 ERA and 2.99 FIP, adding another 20 saves (including his 400th, on May 10) in 23 attempts, and making his first All-Star team since 2018 (and fourth overall).

Jansen is throwing his cutter 82.2% of the time, his highest rate since 2018, and it helps that his 94.3 mph average velocity for the pitch is as high as it’s been since 2014, up 2.1 mph from last year and 3.4 mph from 2020, when he was a bystander as Julio Urías closed out the World Series for the Dodgers — a blow that led him to seek therapy and address his mental health, which helped his rebound. He hasn’t been as dominant as Kimbrel this year, striking out just 28% of hitters, but his home run rate (0.58 per nine) is half of Kimbrel’s, and he’s giving up far less hard contact (3.7% to 10.5% in barrel rate, 31.7% vs. 50% in hard-hit rate). He’s been leapfrogged by Kimbrel in the R-JAWS rankings, but he’s projected to climb to 12th this year, overtaking Hall of Famer Lee Smith as well as Rodríguez, and it’s not out of the question he could crack the top 10. Like Kimbrel, if he keeps it together for another couple of seasons, he could wind up in Wagner territory. Particularly given his durability, 500 saves isn’t out of the question, and that might be enough to put him in Cooperstown.

One other thing of note: Wagner’s 903 innings would be the fewest of any enshrined reliever, and at a 900-inning cutoff, he owns the lowest batting average allowed (.187) and highest strikeout rate (33.2%). Throughout his candidacy I’ve resisted comparing him to this cohort because of their smaller workloads, but if we lower the cutoff to 800 innings, a threshold Jansen reached in his last appearance before the All-Star break, his .182 batting average allowed and 36.2% strikeout rate supplant Wagner. Lower the bar to 700 innings and Kimbrel (who has 727.1 innings) has the edge with a .164 batting average allowed and a 39.9% strikeout rate. For both active pitchers, it seems clear that they’ll have to resist regression while amassing more innings to take Wagner’s titles away.

Injury, illness, and misadventure — most notably, an infected tattoo on his leg and then a no-show for a mandatory postseason workout — limited Chapman to just 104.1 innings from 2020-22. Not only did he lose his job as the Yankees’ closer, he burned his last bridge in the Bronx. After signing for just $3.75 million plus incentives with the Royals, the 35-year-old lefty pitched well enough in a setup capacity to be traded to the Rangers earlier this month.

With a fastball that’s once again humming along at an average of 99.3 mph — up 1.8 mph from last year, and his highest mark since 2017 — Chapman has pitched to a 2.04 ERA and 1.42 FIP in 35.1 innings. He’s striking out 44.4% of hitters, his highest full-season rate since 2014, and hasn’t allowed a homer yet; he’s stifled hard contact (1.7% barrel rate, 30.5% hard-hit rate, .181 xSLG). He’s still pitching mainly in a setup capacity, and so he has just three saves this year and 318 overall. Given his checkered history, which includes a 30-game domestic violence suspension from 2016, it’s an open question as to whether a team will commit to him as a full-time closer again; if not, the 400-save milestone is out of reach. He’s just 25th in the R-JAWS rankings, though the projections would take him to 18th before season’s end. Still, I’m skeptical he’ll have the staying power to mount a serious challenge for the Hall, as I don’t think he has enough goodwill banked within the game to withstand an eventual decline in performance, to say nothing of the way voters may treat him in light of his suspension.

With just 169 career saves, the 38-year-old Robertson doesn’t really stand a chance at eventual election, because he’s spent the bulk of his career as a setup man; only six times has he cracked double digits in saves, and only three times has he notched more than 20. A good number of Hall voters are increasingly wary of closers, so I wouldn’t hold my breath waiting for them to elect a setup man.

Still, it’s worth noting that Robertson currently ranks 21st in R-JAWS — ahead of Chapman and Bruce Sutter, the lowest-ranked Hall of Famer — because he’s been excellent in higher-leverage situations over the course of his 15-year career. Filling in for the injured Edwin Díaz as the Mets’ primary closer, he’s posted a 1.96 ERA and 29.2% strikeout rate while notching 12 saves in 41.1 innings thus far. He’s having the best season of the four relievers here in terms of WAR, and his 1.5 R-JAWS is second to Kimbrel’s 1.6. Odds are that come August 1, he’ll be changing uniforms; he’ll help whichever team acquires him, but that won’t change his fate as far as election is concerned.

How bare is the cupboard beyond these four active relievers? The next-highest-ranked one among those who have pitched in 2023 is Josh Hader, who in his age-29 season has 11.5 R-JAWS. Suffice to say it will be awhile before we can take his candidacy seriously.