The Powerful Dustin Ackley

One of the most promising stories to come out of the Mariners' 2014 season was the development of Dustin Ackley. After two years of disappointing performances he was able to put together a decent season. The Mariners will be counting on him in left field next year and we're all hoping he's turned a corner in his career. But were the improvements he's made this year sustainable?

In my review of the outfielders on the Mariners' 40-man roster, I briefly touched on some of the improvements Ackley made this past year. He was able to hit his line drives and fly balls for more power leading to more extra base hits. He also reduced the number of rolled-over, weak grounders to the left side. Tony Blengino wrote a much more in-depth piece on Ackley's batted ball profile for FanGraphs back in September -- check it out if you're interested in what he came up with.

Back in 2009, Dustin Ackley was a Junior at the University of North Carolina and scouts were drooling over his future major league career.

"Ackley might be the best pure hitter in the college ranks, if not the entire Draft class. He's got great bat control and plus bat speed that allows him to make consistent contact to all fields. There's some debate about how much power he'll have, but that's really only an issue if he can't return to center field. He's had to play first since Tommy John surgery last summer. But regardless of where he plays, those hitting skills should get him off the board early."

-MLB.com

I'd like to try and evaluate one of the concrete hitting skills mentioned in that scouting report above, bat control. Kiley McDaniel recently ran a seven part examination of the way scouts evaluate the mysterious hit tool -- in part two, he explained what bat control means. In short, it's a batter's ability to adapt their swing to match the pitch that's being thrown -- both the location and the speed of the pitch. A batter with great bat control not only runs high contact rates, they're also able to make hard contact to all fields. Ichrio is the perfect example of a batter who has incredible bat control. Justin Smoak has terrible bat control.

Dustin Ackley didn't seem like he had great bat control the past two years but showed real improvement in this area in 2014. Baseball Reference includes a statistic in their batter splits called sOPS+: it measures the batter's OPS against the league average for that split. Here's Dustin Ackley's batted ball location splits for the last three years:

Ackley has always been able to spray the ball from foul line to foul line but, this year, he was able to dramatically improve his results when he pulled the ball and when he hit it back up the middle. Being able to hit to all fields means nothing if they're weakly hit. Ackley was able to hit to all fields with authority in 2014, a skill he hadn't shown since his initial call-up in 2011. Observe his spray charts from the last two years:

And the same spray chart sorted by hit result:

Notice that group of extra base hits that are clumped together in the right-center field gap? That's visible gap power and it had been missing from Ackley's game until this year. This is our second piece of evidence that Ackley was hitting the ball with more authority in 2014.

What about Ackley's batted ball distance? If he was making solid contact more often this year, surely it would mean he was hitting the ball farther. Baseball Heat Maps shows a steady improvement over the last two years:

Or, if you prefer numbers:

Ackley has actually steadily increased his average batted ball distance every year since his first year in the majors. An average of 275 ft. puts him in the company of players like Yoenis Cespedes, Howie Kendrick, and Pablo Sandoval. Now we have our third piece of evidence for an improved Dustin Ackley.

The most dramatic improvement Dustin Ackley made in 2014 might be his performance when hitting fly balls. Blengino talks about this in his article above but here are the relevant splits from Baseball Reference to put things in perspective:

Wow, it looks like the bellwether that we should be looking for next year might be his batted ball performance on fly balls. Deeper fly balls that are hit hard fall in for extra base hits more often. This confirms what Blengino was talking about in his article above. If Dustin Ackley is truly showing improved bat control, this is where we need to look next year to see if he has carried over the improvements he made this year.

Russell Carleton (AKA Pizza Cutter) has done a lot of research on stabilization points for baseball statistics (at what point to statistics become reliable?). After just 80 balls in play, ground ball rates and fly ball rates stabilize. After just 50 fly balls, home runs per fly ball stabilizes. We don't have a stabilization point for batted ball distance, but it makes sense that it would stabilize around the same point as a batter's home run rate (I don't have the math acumen nor the time to figure this out, save it for later). By the end of April, we should have a good idea of how Dustin Ackley is doing in these areas next year.

Steamer sees Ackley's walk rate bouncing back to over 8% but his power regressing to an ISO of .135 next year. If Ackley is able to maintain his batted ball distance gains, he'll probably beat his ISO projection. I don't know if I buy the rebound in plate discipline. Based on his plate approach in the second half of this year, Ackley's walk rate could be a casualty of his rediscovered bat control -- aggressively punishing pitches on the inner half of the strike zone and a better understanding of what he has to do to control the outer half. Overall, I think Steamer has Ackley's overall offensive value pegged pretty close to the mark -- a batter who is just above average with a bit of upside. Nothing to exciting but a far cry from what we've seen from Ackley in the past.