What the hell happened to Austin Jackson?

On July 31st, when we'd heard that Nick Franklin had been traded away for Austin Jackson, most of us were pretty excited. Franklin had become a fairly superfluous piece who had largely lost his luster, and the Mariners desperately needed some help in the outfield. Jackson appeared to be a 2-3 win player who was under club control through next year. He'd had a bit of a downturn this season, compared to his performances in 2012 and 2013, but he was still a solid center fielder with an average/above average bat. This appeared to represent a significant upgrade over what the Mariners currently had (James Jones or Endy Chavez). BUT NO.

In July, Jackson hit .349/.390/.505 with the Tigers. Then, upon joining Seattle, he promptly went into a massive offensive slump that lasted the remainder of the season. Look at his ISO with the M's. Look at it! Maybe you can't see it because you don't have a magnifying glass handy, but let me assure you that it's miserable. In 236 PA with the Mariners, Jackson racked up SIX extra base hits. This was a man who'd averaged an XBH every 12 PA over the past two and a half seasons and then all of a sudden he couldn't hit the ball out of the infield. He also started striking out a lot more and walking a lot less. This was a shocking, disappointing, frustrating turn of events. But what happened?

My first thought was that maybe Jackson was simply struggling to hit away from Comerica Park. Detroit's stadium is rated as a significantly more hitter-friendly park than Safeco. Surprisingly, in 2012 and 2013, Jackson actually hit better on the road (117 wRC+ at home vs. 125 wRC+ on the road). This year, however, he did struggle to hit away from Comerica.

This is a lot of information to take in, but it's pretty clear that Jackson struggled to hit when he was outside of Michigan. All of his stats were significantly better at Comerica Park. This likely explains some of his downturn after the trade deadline, but probably not all of it...

The thing about these numbers that I find to be the most striking is Jackson's GB/FB ratio after leaving the Tigers. Jackson went from a GB/FB ratio of 0.98 with the Tigers (23rd percentile for GB rate in 2014) to a ratio of 2.16 with the Mariners (90th percentile for GB rate). I should point out that Jackson's career GB:FB (GB:FB of 1.33) isn't quite as flyball-heavy as it was at the beginning of this year, but the dramatic change in his numbers after joining the M's is more or less unfathomable to me. Park effects can certainly impact a player's performance, but that is just absurd. (Also, according to Fangraphs, the difference between the park effects for groundballs at Safeco and Comerica is negligible.)

This might have been tolerable if Jackson had transformed into a slap-happy hitter who piled up a bunch of singles (which one might expect to happen with his speed and elevated GB:FB rate), but Jackson's batting average and BABIP also decreased significantly once he joined the M's.

There are lots of factors that could've contributed to the Hindenburg-esque trajectory of Jackson's 2014 season. Maybe he's afraid of salt water and evergreen trees. Maybe his swing just got all funky (though I'd imagine Lloyd, who was his hitting coach for the last several years, probably would've been able to help him with that). Or maybe he simply struggled to adapt to a new city. Unfortunately, it'd be virtually impossible to quantify any of these things. What we can do, however, is look for changes in Jackson's approach.

Here we can see that upon joining the Mariners, Jackson did become more of a pull hitter. This is interesting because the approach pitchers used against him didn't really change (keeping the ball down and away). If he started to hit the ball to the shortstop more often, as opposed to through a hole on the right side of the infield, this could also help explain his reduction in production. His swing rate stayed pretty constant, but it only did so because he started swinging at more balls and looking at more strikes. That is not generally a good combination. Add in the fact that his contact rate dipped fairly significantly and it's no wonder his strike out rate rose by 25%. And even when Jackson was able to make contact, he had trouble driving the ball for a base hit.

Jackson had very little success against anything on the outer part of the plate once he joined the M's (he hit .241 against pitches in the middle and outer third). This is surprising because that was actually one of his strong suits this year with the Tigers, where he hit .318 against those same types of pitches.

This plot shows that, in August in September, there wasn't any region below the numbers where Jackson wasn't super proficient at pounding the ball into the ground. As a result of his inability to get under the ball and deliver any pop, it's not surprising that his spray chart would shrink significantly.

(I guess I forgot to label these. The image where he hits more than zero homeruns is from the earlier part of the season when he was with the Tigers.)

We can see that despite his propensity to pull the ball with the M's, Jackson's pull power in Seattle evaporated entirely and he struggled to hit the ball into the outfield in any direction. According to baseballheatmaps, Jackson's average batted ball distance in 2014 with the Tigers was 207 feet, whereas his average distance with the Mariners was only 160 feet. That is a dramatic decrease in the quality of his contact. Of course his overall batted ball distance is going to decrease with an increased groundball rate, but even the balls he was hitting to the outfield didn't travel as far. (Jackson didn't  hit a ball more than 335 feet with the Mariners.) Looking at how this trend developed over the course of the season is pretty alarming.

To me, this looks like the kind of plot you might expect from a player who was struggling with a nagging injury that just kept getting worse and worse as the season progressed. Or maybe their conditioning was insufficient and they just wore out as the season came to a close. Jackson has been a bit of a first-half  player throughout his career (109 wRC+ in the first half vs 96 wRC+ in the second half), but his decline has never been anywhere as precipitous as it was this year.

So... I don't know. Something happened. Or maybe a lot of little somethings happened. Whatever it was/is, Jackson struggled mightily to hit the ball with any authority whatsoever in the last two months of 2014. These struggles probably caused him to start pressing a little bit, which led to an increased number of bad swings at bad pitches and his elevated strikeout rate. Baseball is hard; when things start to go south it's easy for them to snowball and it can be exceedingly difficult to right the ship.

I assume that the Mariners have a much better idea about what's going on than I do and that they'll work towards fixing Jackson's problem(s) this offseason. The M's are already pretty thin in the outfield, so a version of Austin Jackson that puts up even 85% of his career averages would hugely benefit this team moving forward. Additionally, 2015 is Jackson's final year of arbitration. Last year, coming off of a 3 win season he earned $6 million. Despite his terrible performance down the stretch in 2014, he's still likely looking at a fairly significant raise next year (maybe ~$8 million?). For him to be worth that, he has to turn things around. Here's to hoping that he does.

Go M's.