Luke Jackson

Jackson was a good illustration of how difficult projecting reliever performance on a yearly basis can be. After posting a 6.84 ERA in 2020, Jackson posted a career-best 1.98 ERA paired with 31 holds in 2021. A 90.2% left on base rate was in part responsible for the excellent numbers, but Jackson still posted a combination of skills that often lead to success for relievers. He managed a 26.8 K% while also limiting opposing hitters to a 0.9 HR/9 thanks to a 52.5 GB%. While Jackson was trusted in a high-leverage role, his 11.1 BB% is a significant blemish in his skill profile that has largely prevented him from picking up saves throughout his career. He gained increased competition for late-inning work when Atlanta signed Kenley Jansen in mid-March, and Jackson will miss significant time after being diagnosed with a torn UCL in early April.

If you are still new to the fantasy game, there is a concept in baseball known as reliever volatility. The concept is that a reliever can go from dominance to irrelevance in a flash. There are many examples of this, with Jackson being a very recent example. In 2019, Jackson struck out 33.7% of the hitters he faced with an elite 25.4 K-BB% looking every bit like a reliever ready to take the next step. He had a rough summer which translated into a bad 2020 where his strikeout rate fell to 15.2% and that elite K-BB% plunged 20 full percentage points. This past season's problems were all about awful outcomes with his primary pitch, the slider, although the actual BA on the pitch (.358) was well above the expected average of .267. He fell behind in too many counts and had to overuse his hittable four-seamer, thus the quick change from high- to low-leverage work.

Jackson was in the 90th percentile for his fastball velocity and strikeout rate in 2019, and the Braves believed in him so much they went out and traded for Shane Greene and Chris Martin and gave native Georgian Will Smith a big three-year deal. Jackson throws with a lot of velocity, but it's his slider that makes or breaks him. He blew seven of his 25 save chances last year, serving up 10 home runs in 72.2 innings of work. That is what ultimately did him in -- the increased velocity and the improved walk rate from 2018 were nice to see, but closers simply cannot allow home runs at a high rate and expect to keep their job on a contending ballclub. That, and the problems Jackson has had against righties despite the great slider. Reverse splits aren't a thing, but Jackson is certainly trying to disprove that. Kiss goodbye to the saves.

Jackson was expected to compete for a spot in the Rangers bullpen out of spring training, but some recurring back problems held him out for the bulk of the spring slate, leaving the Rangers brass no choice but to send him back to the minors. He performed well during his time at Triple-A Round Rock, piecing together a 2.45 ERA and 11.1 K/9 in 22 innings out of the bullpen. This helped him garner a couple of brief cups of coffee in Arlington, although he pitched horrifically against major league hitters. In 11.2 innings, the electric 25-year-old was shelled for 14 runs on 22 hits (four home runs) while compiling a dreary 3:8 K:BB, leading to a demotion all the way to Double-A Frisco. Jackson has a lot of life on his mid-90s fastball, but his below-average command and control have limited his ability to compete for a high-leverage role thus far. The Braves saw an opportunity to swap declining assets with Texas this offseason, acquiring Jackson in a deal that sent another failed prospect, Tyrell Jenkins, to the Rangers. The trade should offer Jackson a better chance to break camp in the majors, given the Braves' lack of quality bullpen depth.

Jackson began the year at Triple-A, where he posted a decent performance that was a big improvement from his disastrous debut at Round Rock in 2014, where he was converted to relief after five poor starts to the season. Jackson's plus fastball and shaky command seemed to always hint at a reliever role, and it appears that Texas has elected to go that route. He made seven appearances out of the Texas bullpen in 2015, and it will be difficult for him to carve out an Opening Day roster spot in a bullpen that already features Shawn Tolleson, Sam Dyson, Keone Kela and the newly-acquired Tom Wilhelmsen from the right-side.

The 6-foot-2 righty enjoyed a 3.02 ERA and 0.98 WHIP with a 83:24 K:BB ratio in 83.1 innings at Double-A Frisco, but that excitement was short lived, as Jackson gave up 46 earned runs in 40 innings (10.35 ERA) following his promotion to Triple-A Round Rock. His HR/9 rate quadrupled and his BABIP ballooned to almost .400, so there was some bad luck involved with his disastrous turn at Round Rock, but posting a career-high 13.9% walk rate did not help matters. The stretch at Frisco was the best run of Jackson’s career, and it’s likely that his performance at Round Rock simply qualifies as a minor setback. A strong start to 2015 at Triple-A could place him in the Rangers’ rotation this summer. Entering his age-23 season, Jackson still possesses a fastball that borders on double-plus, with a curveball and changeup that also have plus potential, so the worst-case scenario here is that he ends up pitching the eighth or ninth inning in Arlington.

Jackson began the year repeating a stint at High-A, but ended the year with 27 innings at Double-A Frisco. There are questions about the repeatable nature of his high-effort delivery, and some related questions about the consistency of his breaking pitches as a result, which could limit his future to a late-inning option out of the bullpen. It's a role that he might eventually pitch his way into, but he'll be given every opportunity to succeed in the rotation first. He's expected to begin the year in the rotation at Double-A Frisco.