The Phillies have 4 hitters with at least 20 home runs this year, two of them (Rhys Hoskins and Dylan Cozens) are obvious power threats and Scott Kingery is having a breakout season, but it is the guy tied for the lead that might be the most interesting. The Phillies selected Mitch Walding in the 5th round of the 2011 draft and signed him for the 2nd highest bonus in their draft class. I wrote about pending minor league free agents for Crashburn Alley earlier this week, and Walding joins the pair of pitchers (Rios and Therrien) as well as fellow Reading prospects Carlos Tocci and Jiandido Tromp as notable players with that distinction. As of today, Walding is batting .236/.334/.532 with 22 home runs.
Walding had a bit of a breakout last year due to a swing change. He added more uppercut to his swing, which caused a large jump in HR/FB rate. Walding saw his season high for home runs go from 7 to 13, and it earned him a promotion to Reading for the stretch. Walding has seen his home run rate jump again, so what has caused the new breakout?
Let’s start in the obvious place. Reading. Here is Walding’s HR/FB rate over the past two seasons:
2016 Clearwater: 10.3%
2016 Reading: 23.1%
2017 Reading: 24.2%
Now the 2016 Reading value is small sample size, and I don’t know if it is reliable. However, the 2017 Reading value is well over double the value it was in Clearwater. There has been some whispers that the changes to the ball have reached the minors, but let’s throw that out for right now and deal with what we know. Walding currently leads the Eastern League in HR/FB rate. His rate however is below Dylan Cozens in 2016 by a good bit. Now HR/FB rate over all of his time in AA is not a great way to judge this alone, so here are Walding’s Home/Road splits.
| AB | 2B | 3B | HR | |
| Home | 121 | 3 | 3 | 15 |
| Away | 163 | 7 | 1 | 7 |
We unfortunately don’t have HR/FB rate for the H/R split here. But we do see a huge home run discrepancy, but not enough to say that Reading is causing all of the power spike. The other problem with doing just home/road splits for the affect of Reading is because this is still all mostly small sample size, and we see this even more when we break down Walding’s home runs by month.
April: 3
May: 3
June: 13
July: 3
Is Reading only affecting a single month of results? Highly unlikely, and we see that it was an 8-5 split on he month, which is actually less favorable for Reading than his full year numbers.
So what is causing this home run spike? The answer is fairly simple if we go through a few more numbers. The first thing that could cause a home run spike is more balls in play. Last year Walding walked at a 12.6% rate and struck out at a 26.7% or 39.3% of his PAs ended with the ball not in play. In 2017, those numbers are 12.2% and 31.9% or the ball is not in play for 44.1% of plate appearances. So he is actually putting the ball in play less thanks to an increase in strikeout rate. The answer then must be that he is putting the ball in the air more than he did last year. This is indeed our solution, as Walding has a fly ball rate of 51.4% this year, up from 40.1% in Clearwater and 31.0% in Reading last year. He has seen a drop in BABIP from Clearwater (an 88 point drop from .371 to .283) as he has run into more outs in the air, but the home runs have kept his batting average respectable despite the drop.
So what do the Phillies do about Walding going forward? It is a tough decision because he is the only third baseman in the upper levels of the system if for some reason they move on from Maikel Franco. Walding even comes with a reputation for being a pretty good defender, and he has gotten some work in at first and left field in the past. The problem is he is still only hitting .236 which drives down his on base percentage, and his strikeout rate is alarming. Walding also turns 25 this September (he is barely younger than Maikel Franco). He has also shown some pretty heavy left/right splits. Given the 40 man roster situation, giving Walding a 40 man roster spot seems dangerous to roster construction. However, if the Phillies can bring him back with a spring training invite to have him go to AAA and try to be a 4 corners bench player with pop, they might have something here.