Boston Red Sox: Using Wade Davis as a roadmap for Joe Kelly
After a failed stint as a starter for the Red Sox, Joe Kelly looks to have the stuff to become a shutdown reliever — a similar trajectory to Wade Davis.
The Joe Kelly Experiment hasn’t gone as planned for the Boston Red Sox since former GM Ben Cherington acquired him at the deadline in 2014.
In 55 games spanning 41 starts, Kelly has posted a 4.70 ERA with a 1.45 WHIP across 235.2 uninspiring innings. Adding to the frustration, the now 28-year old features a flamethrower of a fastball and a devastating slider along with a plus curveball. With such nasty stuff, Kelly has become somewhat of an enigma over his Boston tenure, but something may have clicked in 2016.
It started with a role change to the bullpen. The logic for such a move was sound and probably long overdue. In the pen, Kelly could pump up the fastball velocity from a normal 93-96 to an elite 98-101 miles per hour. He could also eliminate his work-in-progress changeup (that was getting beaten around to a tune of a .308 batting average) and focus on his two breaking balls as his offspeed offerings.
The results were immediate and drastic; Kelly’s second half ERA dropped to a minuscule 1.02 after posting a gruesome 8.46 ERA in the first half. His WHIP literally halved and his SO/BB ratio more than doubled. He held opposing batters to a .203/.261/.297 slash line, and the positive numbers go on and on.
In short, Kelly was nothing short of dominant in his new role. Perhaps the most encouraging sign is that there is recent precedent for a failed-starter-turned-star-reliever. He plays for the Kansas City Royals, and his name is Wade Davis.
The Wade Davis story is a well-known one: in 2013 he was a mediocre starter on the Royals, an insignificant add-on to the James Shields–Wil Myers swap, posting a 5.32 ERA. One year later, he was arguably the most dominant reliever in the game, with an ERA of just 1.00 along with peripherals such as his 13.63 K/9 and his 0.40 HR/9. What did Davis do to become such a late-game force, and how can Kelly learn from it to complete the transition for himself?
As mentioned before, the transition to the bullpen itself can be a boon for production. Fewer innings means increased velocity and movement, and stuff just gets nastier. This was certainly the case for Davis, as opposing hitters who were hitting .331 off his cutter as a starter were now getting obliterated to a .106 clip. His curveball’s opposing average of .304 sunk to just .224. The .488 changeup was cut out entirely, as was the .337 two-seam fastball. Wade Davis’s pitch selection became more streamlined, focusing on what made him successful in the past and improving with higher velocity.
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Kelly showed a similar trend in his run of bullpen dominance in the second half of 2016. He, too, cut out his lackluster changeup and limited his offerings to his plus-fastball and his two breaking balls. As a reliever, it’s easy to get away with a limited pitch selection due to the fact that hitters only see the reliever for one at-bat in a given game, while a starter can feature two or three at-bats. With inexperience comes unpredictability, and that’s what makes relievers like Davis, Kimbrel, Betances, Chapman, Miller, and the like so unhittable.
Kelly has seen what Davis did to thrive in his new role, and the results are already tangible. Fangraph’s PITCHf/x data lets us take a deeper look into how Kelly threw, and how hitters reacted to his pitches.
| Year | O-Swing% | Z-Swing% | Swing% | O-Contact% | Z-Contact% | Contact% | Zone% | Pace |
| 2015 | 25.1% | 59.6% | 41.8% | 64.0% | 90.4% | 82.2% | 48.4% | 23.0 |
| 2016 | 28.4% | 60.3% | 42.1% | 56.7% | 86.9% | 75.2% | 42.9% | 25.8 |
In short, Kelly has gotten more swings and less contact from opposition. More hitters are liable to swinging at his pitches outside the zone and well as inside the zone, but the contact rates for both situations have dropped at the same time. That’s a lethal combination that results in Wade Davis-like high strikeouts and low walks.
Perhaps it’s too bold and too soon to declare Joe Kelly the next Wade Davis. The similarity in repertoire and adjustments have shown a glimpse of what could be, but it’s up to Kelly to get there. For every Wade Davis or Andrew Miller, there’s a couple of guys who have the stuff but just can’t figure it out. It remains to be seen which side of the coin Joe Kelly will land on, but the sheer upside is enough to warrant a spot in the back-end of the Boston bullpen.
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