Jake Arrieta Is a Cub Again

For the second time in his career, Jake Arrieta will join a rebuilding Cubs team. The soon-to-be 35-year-old righty spent four seasons and change with the Cubs from mid-2013 to ’17, joining a team en route to 96 losses and helping Chicago to four straight playoff berths, including a long-awaited championship in 2016. During that stretch he emerged as an ace, throwing a pair of no-hitters and winning a Cy Young. This time around, he’s trying to re-establish himself as a reliable starter via a one-year, $6 million deal, that for a team that’s in the process of blowing up the roster that won the NL Central in the abbreviated 2020 season.

The contract is a big step down from the complex three-year, $75 million deal Arrieta just completed with the Phillies, but then he struggled mightily while trying to live up to that contract. Over the course of those three seasons, he delivered a 4.36 ERA, 4.55 FIP and 3.7 WAR in 352.2 innings, making a full complement of starts only in 2018. The recurrence of a bone spur in his right elbow, which had bothered him the previous year as well, limited him to 24 starts in 2019 before he underwent season-ending surgery in mid-August. While Arrieta could have opted out and sought a larger payday at that juncture, it clearly wasn’t in the cards for him amid the diminishing returns.

Those returns continued to diminish in 2020, as Arrieta made just nine starts before being shut down in mid-September due to a right hamstring strain. His 5.08 ERA was his highest mark since 2012, when he was still trying to find himself with the Orioles; the season was his fifth straight with an ERA that increased from the previous year. He broke a similar streak in the FIP department with a 4.66 mark, down from 4.89 in 2019 and in the vicinity of league average (101 FIP-).

As far as trends go, most worrisome is his combination of declining sinker velocity and strikeout rate. Here it is seasonally:

And here’s his rolling 15-game average:

Where Arrieta’s sinker — which he threw 43.1% of the time in 2015, 60.9% of the time in ’16, and more than half the time since — has declined from a peak of 95.3 mph in ’15 to 92.5 mph last year, his strikeout rate has fallen from 27.1% in ’15 to 16.8% last year, eroding a bit every year.

Arrieta has been able to mitigate this a bit by keeping the ball on the ground with regularity, generating more than twice as many groundballs as fly balls, but his home run rates have nonetheless been above 1.2 per nine in three of the past four seasons. His xwOBA figures by percentile tell a grim story, as he’s dropped from the 96th in 2015 to the 74th, 60th, 40th, 23rd, and 14th in the successive seasons. This does not suggest a pitcher poised to summon his glory days in his return.

It’s turned out to be a brutal free-agent market for starting pitchers, with Trevor Bauer, Mike Minor, and KBO returnee Chris Flexen the only ones to land multiyear deals. Even then, Arrieta’s $6 million guarantee comes in below those of several pitchers who are younger but have spottier resumés:

• Robbie Ray, heading into his age-29 season, signed for $8 million with Toronto after being torched for a 6.62 ERA and 6.50 FIP in 51.2 innings with the Diamondbacks and Blue Jays;
• Anthony DeSclafani, heading into his age-31 season, signed for $6 million plus incentives with the Giants after being rocked for a 7.22 ERA and 6.10 FIP in 33.2 innings with the Reds;
• James Paxton, heading into his age-32 season, signed for $8.5 million with the Mariners after a season in which back surgery and then a flexor strain limited him to five starts and a 6.64 ERA, not to mention a 2.9-mph drop in average fastball velocity;
• Drew Smyly, also heading into his age-32 season, signed for $11 million with the Braves after being limited to 26.1 innings due to a finger injury, that following a 114-inning, 6.24-ERA season;
• José Quintana, yet another pitcher heading into his age-32 season, signed for $8 million with the Angels after being limited to 10 innings by thumb and lat injuries;
• Chris Archer, one more heading into his age-32 season, signed for $6.5 million with the Rays after missing all of 2020 due to surgery to repair thoracic outlet syndrome and, before that, compiled a 5.19 ERA and 5.02 FIP in 119 innings with the Pirates;
• Garrett Richards, heading into his age-33 season, signed for $10 million with the Red Sox after making 10 starts for just the second time in the last five seasons.

That list doesn’t include Marcus Stroman and Kevin Gausman, both of whom wound up in the right place at the right time to receive and accept $18 million qualifying offers. Nor did I add two-time Cy Young winner Corey Kluber, who signed for $12 million with the Yankees after throwing just one inning in 2020 due to a teres major strain and 36.2 innings over the past two seasons.

On the one hand, you might assume that Arrieta took some kind of hometown discount to return to Chicago given his modest salary relative to the above. But on the other hand, the reality is that via his age and performance, his projection isn’t very rosy:

I threw Kluber, who’s five weeks younger than Arrieta, into the table as well as Lester, who’s 22 months older and who couldn’t even get the Cubs to match the deal he signed with the Nationals three weeks ago. Based on the projections, Arrieta actually appears to be getting the benefit of the doubt based on his resumé. Those younger pitchers are forecast to be two or three times as valuable for only slightly more money; on a per-win basis, Arrieta — whose group-low strikeout rate goes hand in hand with his meager projection — might reasonably be expected to make even less.

That said, it’s also worth noting that the pitchers who turn up as the priciest here on a per-win basis are the ones projected for lower innings totals due to age and injury histories. There’s a lot of dart throwing that comes with estimating playing time in general; for example, about half the pitchers who get surgery to correct thoracic outlet syndrome throw fewer than 140 innings through the remainder of their careers.

Anyway, with the Cubs, Arrieta joins a significantly restructured rotation. Driven by a Cy Young-caliber season from Yu Darvish and a typically excellent campaign from Kyle Hendricks, the unit ranked seventh in the majors in WAR last year and helped the team win the NL Central. Yet despite that, team owner Tom Ricketts decided to start tearing up the roster in the face of allegedly “biblical” financial losses. Darvish was traded to the Padres in a salary dump. Lester, Quintana, and Tyler Chatwood, none of whom had much to do with the rotation’s success in 2020 — Lester was barely better than replacement level, and the other two made one and five starts, respectively — all departed via free agency, with the last of those landing in Toronto. Hendricks is still around, but only he and Zach Davies, who was acquired in the Darvish trade, project to be above average. Alec Mills, whose otherwise pedestrian season was highlighted by a no-hitter in mid-September, and Trevor Williams, who fell so far from his strong 2017–18 showings that he was DFA’d and released by the Pirates in November, will round out the rotation along with Arrieta. That newly restructured group projects to have the majors’ third-lowest WAR according to our Depth Charts.

The Cubs have also shed several other key players from last year’s roster, including relievers Jeremy Jeffress and Ryan Tepera, catcher Victor Caratini, second baseman Jason Kipnis, and outfielder Kyle Schwarber. Not all of them had good 2020 seasons; indeed, subpar performances made it easier to part with Schwarber, Caratini, and some other players, such as Albert Almora Jr. and José Martínez, who might have had futures on the North Side. The retooling has been modest, with Chicago bringing in the likes of Joc Pederson, Jake Marisnick, Davies, and now Arrieta.

As currently constructed, the team is forecast for 79.1 wins and a third-place finish in a division where the top projection, that of the Cardinals, is for just 81.5 wins. Even in this denuded state, the Cubs are, in theory, contenders. But if any of the numerous trade rumors centering around Willson Contreras and Kris Bryant come to pass, that projected win total is likely to drop. Arrieta could find himself trying to turn his career around while surrounded by a 90-something loss team. It wouldn’t quite be full circle — things aren’t so dire that he’s an Oriole again — but both he and the Cubs will be a long way from 2016.