Given the Braves currently wield the National League’s second-most productive bullpen (and MLB’s fifth-best) so far this season, in terms of FanGraphs WAR (2.5 WAR), there really isn’t much to complain about when it comes to the team’s relief core. Of the nine Braves’ relievers to tally at least ten innings in 2020, seven currently sport a sub-2.50 ERA, and the group’s highest mark stands at just a 4.24 ERA — owned by Luke Jackson, entering Thursday evening’s series opener with the Nationals.
And in any other season, there probably wouldn’t be much concern regarding Jackson’s still-acceptable ERA. In fact, looking at his 3.47 FIP, there’s a case to be made that perhaps Jackson is just fine and is experiencing a run of bad luck so far this season. However, when digging a little deeper into the 29-year-old’s numbers for 2020, there are a few aspects of Jackson’s game that raise a red flag…
A large decline in strikeouts
Among Braves’ relief pitchers who logged at least 20 innings in 2019, Jackson’s 33.7 K% was tops on the team as he finished the year with 13.13 strikeouts per nine and a K/BB ratio of 4.08. With both a slider and curve that put away a third of the batters he faced, the former first-round pick put together a career-year, accruing 72.2 innings — pitched across 70 appearances, while posting a 3.24 ERA — good for a 1.3-WAR season (nearly twice as many WAR as the team’s second-most productive reliever, Mark Melancon).
But the decline in strikeouts for Jackson this season has been drastic. In 2020, that elite strikeout-rate from 2019 has fallen to just 13.1%, which is good for last on the team right now, when examining Braves’ relievers with 10+ innings. Jackson’s strikeouts per nine has also fallen to just 5.92 batters per nine, and his 1.22 K/BB ratio illustrates more than anything else that this is one of the Braves’ worst relievers when it comes to generating punch outs.
But really… how can he suddenly be striking out batters nearly 40% less-often than just a season ago? A lot of Jackson’s problems in 2020 are due to the failures of a particular pitch…
Issues with the slider
For his career, especially since the 2017 season, Jackson’s slider has been one of his primary offerings to put away opposing batters. Going on his fifth major league season, the righty has allowed just a .239 AVG and 75 wRC+ with the pitch, while maintaining a strikeout rate of 32.7%. However, in 2020, Jackson’s slide-piece has essentially been his worst offering.
With a .364 AVG and .455 SLG% so far, opposing batters are running a 141 wRC+ versus Jackson’s slider, and pouring salt on the wound, even with two strikes, no one’s missing it. Last season, whenever Jackson got batters to two strikes, it was almost a given that he’d turn to his filthy slider for the punch out (28.1% Put Away rate), but this year, he’s only managing to get that strikeout 11.3% of the time, suggesting his problems with the pitch correlate rather well with Jackson’s overall decline in strikeouts.
You would think there would be some type of silver bullet to explain the problems Jackson’s having with the pitch, but when examining the characteristics of his slider this season, there’s really nothing that stands out. His horizontal movement of 2.2 inches right now is exactly what it was at the conclusion of 2019, and his vertical movement of 41.3 inches is within 1.5 inches relative to last year. Velocity and spin-rate also appear to be consistent with what Jackson was able to do during his breakout season as his slider this year is only a tick slower (86.6 mph compared to 87.7 mph in 2019) and spin just 124 RPM off last season’s mark. A 1-mph decline in velocity and a slight drop in spin-rate isn’t enough to conclude that Jackson has changed anything with the offering. And if you look back to previous seasons, you’ll see that his slider has varied quite a bit in terms of its makeup.
And his lack of success with the slider probably wouldn’t be such a big deal if he had another pitch he could turn to this season, but both Jackson’s fastball (.280 AVG) and curveball (.385 AVG) are also getting knocked around in 2020, leaving him with very little to lean on when things get bad. However, regardless of how well Jackson’s repertoire is trending, if he consistently can’t get ahead in the count, he’ll always be facing an uphill battle…
Problems with first-pitch strikes
MLB pitchers are averaging a first-pitch strike at a 60.6% clip this season, and for much of his career, Jackson has kept his rate right in line (61.6%). However, in 2020, he’s leading off with a strike at an almost career-low rate, only 52.4% of the time (his worst mark since the 2016 season).
Unfortunately, there’s really nothing to take away from his lack of command at the beginning of at-bats, other than perhaps there may be something he’s doing differently strategy-wise than in previous seasons. But it just adds fuel to the fire when a pitcher can’t seem to ever get ahead, and given how poor Jackson’s pitches are performing in 2020, an improvement in first-pitch strikes could be a minimal change that unlocks something more significant for him.
Overall, Jackson should still hold his head high. Despite some concerning underlying numbers, his 2020 stats are actually around average, and the Braves’ bullpen is performing well as a whole. There is also a bright side to his struggles in 2020: Jackson has allowed the lowest Barrel% (1.6%) of his career, ranking third in the majors when excluding ties. Of the 64 batted-balls against him, only one hit has been barreled by an opposing batter. Jackson’s average exit-velocity against him is 89.8 mph (just a smidgen above the MLB average).
At least for now, thanks to an ultra-deep bullpen, manager Brian Snitker can keep Jackson in many more lower-leverage situations until he can start turning the corner (so far Jackson has logged 11.1 of his 17 innings this year in less-crucial scenarios). That will be important going forward as the Braves inch closer and closer to the end of the regular season, for the playoffs will require everyone being at the top of their game. We’ve had to witness Jackson in a funk before, and in seasons prior, his performance wound up costing the Braves several wins. That’s not the case now. Either way, hopefully, the right-hander can get his magic back as the team will need 2019’s filthy slider come October.