How Did The A’s End Up With Baseball’s Most Productive Reliever?

Okay, I’m sure some will take umbrage with the title here. But I chose my words pretty carefully. Liam Hendriks probably wasn’t baseball’s most effective reliever in 2019. He almost assuredly isn’t its best from a true-talent perspective. And the Aussie certainly isn’t its most valuable when it comes to control rights and contracts. (He’ll be a free agent at the end of the 2020 season.)

But … Hendriks did lead Major League Baseball’s bullpen denizens with a whopping 3.8 fWAR last year … the loftiest single-season tally since Eric Gagne’s magical 2003 effort. (It’s 3.9 if you include his two “opener” outings.) Hendriks was also worth 3.5 rWAR, so it wasn’t just a quirk of the FIP-based Fangraphs tabulations. Prefer RA9 WAR? He was even more dominant.

But, you may protest, wins above replacement isn’t the best measure of a reliever. That’s no doubt true. The precise tabulations don’t really matter for our purposes here. Hendriks was in part able to out-WAR his fellow relievers because he threw so many innings — 85 in 75 appearances, one of the heaviest workloads in the game — but that just makes things more impressive. He ranked among the leaders in most major measures of effectiveness as well … including fielding-independent pitching measures FIP (2nd), xFIP (18th), and SIERA (5th).

This showing was exceedingly impressive, no matter the details. It was also … decidedly not consistent with Hendriks’s prior efforts on an MLB mound. Entering the 2019 season, his big league stat sheet reflected 406 innings of 4.72 ERA pitching.

How on earth did we get here?

We can mostly ignore the earliest stage of his career, when Hendriks — once a prospect of some note with the Twins — failed to make it as a starter. The Minnesota organization cut bait after 156 innings of 6.06 ERA pitching. Hendriks ultimately landed with the Blue Jays after a round of offseason waiver-wire musical chairs in the 2013-14 offseason. He first went from the Twins to the Cubs after the Minnesota org signed Phil Hughes. The Orioles prevented the Cubs from slipping Hendriks through waivers but cut him loose when they inked Ubaldo Jimenez.

The Toronto organization only gave Hendriks a few outings during the ensuing 2014 season before sending him to the Royals in a deal for Danny Valencia. Hendriks did have good Triple-A numbers that year. When the Royals needed 40-man space in the ensuing offseason, the Jays stepped back in and grabbed Hendriks back in a DFA limbo swap.

Finally, the stage was set for success. Hendriks moved into the bullpen in Toronto … and immediately exhibited a huge uptick in velocity. He was sitting over 95 mph in a relief capacity and having much more success at generating swings and misses. In 2015, Hendriks turned in 64 2/3 innings of 2.92 ERA ball with 9.9 K/9 against 1.5 BB/9. He didn’t allow many home runs (0.4 per nine) and even generated a strong 46.3% groundball rate (the only time he has ticked up in that department).

The Blue Jays decided to cash in at this point, shipping Hendriks to Oakland in exchange for steady veteran swingman Jesse Chavez. He continued the strong work for the most part. While his ERA trickled north, Hendriks still carried good peripherals and gave the A’s a lot of useful innings in his first two campaigns. Taking his 2015-17 efforts as a whole, Hendriks was a notable contributor: he threw between 64 and 64 2/3 frames in each season while compiling a 3.63 cumulative ERA and a total of 3.9 fWAR (precisely the tally he managed in the 2019 season alone).

Before Hendriks could break out, he had to go through the roughest patch since his time as a starter. He struggled with a groin injury and threw eleven terrible innings before being dumped to make way for Edwin Jackson. Hendriks sailed through waivers and could’ve elected free agency, but decided to stay with the A’s since doing otherwise would’ve meant giving up the remainder of his $1.9MM arbitration salary.

Expectations were low when the A’s unceremoniously brought Hendriks back onto the MLB roster for the stretch run with the September active roster expansion. But he had transformed himself while away and the results were immediately apparent — at both Triple-A (43:4 K/BB in 25 1/3 innings) and the big leagues (two earned runs, 10:3 K/BB in 13 innings). What changed? As Rian Watt of Fangraphs wrote recently, A’s pitching coach Scott Emerson credits Hendriks for having “transformed his body” and with it his “mindset” and “approach” during his demotion. Oh, and Hendriks added velocity — it was apparent late in 2018 and continued in 2019 — and figured out a better means of locating his curve to complement the heat.

That good old-fashioned hard work has served Hendriks well in the past; he credited strength training and clean living for his original, pre-2015 breakout. But this time he moved into much more exclusive territory, delivering a 96.8 mph average fastball and generating a big 17.0% swinging-strike. Hendriks ended up fifth among all relievers with 32.0% K%-BB%.

Remarkably, even as the A’s watched Blake Treinen fall from his perch (a 3.6 fWAR 2018 season), they were able to turn over the ninth inning to a similarly dominant hurler. Hendriks ended up locking up 25 saves for Oakland last year. He’s earning a reasonable $5.3MM in his final season of arbitration eligibility — which will actually be his tenth consecutive season of MLB action, owing to all the ups and downs over the years.

As for the future, we’ll have to see whether Hendriks can keep this going. But he only turned 31 in February, so he could have many good seasons ahead.