Lots of digital ink has been spilled about a fairly insignificant piece of the Braves’ bullpen. My speculation is that it’s been largely influenced by weird Twitter trolls who jokingly refer to Luke Jackson as elite. I get it, it’s funny. He had a heck of a run in the first half of 2019. And if you’re someone who appreciates someone mentally stepping up to take on the role of the closer when they’re clearly not qualified for it, like I am, then you loved the ride, assuming it didn’t create any ulcers.
But 2020 was a very forgettable stretch of games for Luke Jackson. Everything went backwards for him. His strikeout rate plummeted from 13.13/9 in 2019 down to 6.84 in 2020. Walk rate increased by more than a walk per 9. Hard-hit rate increased. His velocity didn’t dip too much, but he did lose over a hundred RPMs off the spin rate of his slider. His slider was his claim to fame in 2019 and earned him the “Sliderman” monicker, and losing that many RPMs is not insignificant. With that said, I’m not sure that’s something he couldn’t get back if he worked on it in the offseason. The good news is the team will know quickly in Spring Training.
There were a couple reasons for optimism in a deeper look into his numbers. He significantly cut down his HR per flyball rate, from 25% in 2019 down to 11% in 2020. His groundball rate did not change much, slightly increasing actually. His left on base percentage also plummeted, and if you believe that your ability to strand runners is largely luck, then maybe you think he was a little unlucky. After 3 straight years of a strand rate in the 70’s, it fell more than 10% down to 60.5% in 2020. You would think that if he could get his slider back (a big “if”), he could get the K’s back, continue to keep fly balls out of the seats, and he might bring the success he had back. It’s not like he was walking a tight-rope in 2019; FIP had him at 3.24 since he was legitimately missing bats and getting outs with that slider.
There is definitely an ideal role for Luke Jackson, and it’s a bargain at his $1.8M. It’s not closer, obviously. But with the glaring issue of starting pitcher endurance dwindling (for instance, our best pitcher Max Fried didn’t get through the 6th inning in 7 of his 11 starts), someone who can come in and pitch both a 5th and 6th inning without giving the game away has tremendous value, both in defeats and in wins. I continue to think that multi-inning middle relievers are a missing piece in modern bullpens considering how effectively they can get through 6-8 hitters in the order one time vs. the starting pitcher attempting to do so for a third time.
And I also like to avoid the roulette wheel of switching out my pitcher, which increases the likelihood that we find a reliever who just “doesn’t have it” that day, which can be almost impossible to predict. Luke Jackson threw more than 25 pitches in 10 of his 19 appearances, so if he can get that slider back, he keeps me off the roulette wheel a couple more times a week. Long story short, I really like a bullpen built with a couple more multi-inning relievers than what we see in today’s game. Luke Jackson, for $1.8M, is a bargain if he’s in that role and doing it well.