The Powerful Dustin Ackley, Revisited

We’re a week and a half into the season and there are few things we know with certainty. What’s going on with Hisashi Iwakuma? Will Justin Ruggiano ever see the field again? One thing we have seen are the boomsticks. Two-thirds of the Mariners’ runs have come off the homer in this young season. We assumed that Nelson Cruz would infuse the Mariners lineup with some much needed power but the real surprise has been Dustin Ackley's three home runs.

Back in November, I examined the improvements Ackley made down the stretch in 2014. In short, last year Ackley improved his production off fly balls by pulling the ball with more authority and distance. Through nine games, we’ve seen Ackley build off those improvements he made last year. Two-thirds of his hits have been for extra-bases and half of them have left the yard. Given this explosive power output, I wanted to revisit what Ackley has done this year and what it could mean for the rest of the year.

The average distance on Ackley’s three home runs this year is 396.33 and they have left the bat at an average speed of 103.5 mph. Both marks are Ackley’s best since 2012. Two of those home runs have come off breaking balls, an area where Ackley has struggled—prior to this year, his ISO on breaking balls was a paltry .105. The other home run Ackley has hit came off an 81 mph "fastball" from Jered Weaver.

Perhaps the most intriguing thing has been the location of the pitches Ackley has hit out. Over the last four years, Ackley has developed a number of holes in his swing. He’s had trouble making solid contact over the outer half of the plate as well as up in the zone. Take a look at this ISO per pitch heatmap:

Ackley has been the most powerful on pitches over the plate, inside, and low. Now, guess where the three pitches he’s hit out were located. Two of them were middle up and the other was low and in. Here’s that same heatmap with the locations of the homers overlaid:

Pitch locations via Baseball Savant

The home run Ackley hit on Opening Day was the first homer of his career that was located in the upper middle quadrant. He’s only hit three other homers that were located on in the outer middle quadrant like the one he hit in Los Angeles.

Obviously, we’re working with the smallest of sample sizes here. Dustin Ackley has put just 16 balls in play this season and certainly won’t keep up his 43% home run per fly ball rate. Still, it’s good to see Ackley hitting for power in areas of the strike zone that he’s traditionally struggled in. It’ll be awhile before his batted ball statistics stabilize for this year. If he continues to hit his fly balls and line drives with authority to right field, we may see further improvement over last year’s numbers.

One other thing to note is the platoon that has Dustin Ackley sitting against most lefties. He's faced a lefty just four times this season and has produced one hit and one strikeout. If he continues to see the majority of his time against righties, his numbers will look much better than if he were a full time player. It would be great to see Ackley make some improvements against lefties as well but I'm satisfied with incremental improvements for now. As long as Rickie Weeks and Justin Ruggiano are on this roster, Lloyd McClendon has few reasons to throw Ackley out there against lefties. If Ackley's improvements at the plate make the strong side of the left field platoon better, that's one less thing to worry about.