Is Justin Upton Injured?

A pair of articles on fangraphs have brought me to the conclusion.  Either Justin Upton has severe mechanical issues or he's hurt and because of that injury, he is displaying severe mechanical issues.  First, in his MASH Report, fantasy sports contributor Jeff Zimmerman sought to introduce a new number called SLOW.  Here is how he explains his arrival at the number.

The basic parameters for the pitches examined are:
1. Pitches thrown into the heart of the plate (I don’t want to look at a chase rate)
2. Fastballs >=92 mph (looking for fastish fastballs)

I created the final metric using a weighted combination of:
1. Contact% (contact with the pitches)
2. Foul% (In play contact)
3. Pull angle on line drives and ground balls (is the hitter hitting the ball late)

Upton leads this season chart by a good deal and has shown the second biggest change since 2012.  Another fantasy contributor followed with an article of his own which goes a little further.  The report is out on Upton and it's not exactly glowing.  According to the numbers, Upton can't hit a fastball even if it's delivered in the strikezone.  As a Braves fan, these numbers provide some clarity to what I thought I saw a lot of.  I don't have a subscription to watch the Braves routinely, nor the time, but when I do watch them, it has seemed that I have witnessed a good deal of Upton swinging through fastballs, even badly placed, in the strikezone.

Now, mechanics could explain all of this.  Sometimes, a hitch develops in a swing and the hitter has considerable trouble getting the bat through the zone.  B.J. Upton, who also appears high on the SLOW list, has well-documented issues with his swing and its timing.  A possible switch to a lighter bat could help, but a bigger issue is that if it is that the younger Upton is having mechanical issues, how much is due to a possible injury?

Fredi Gonzalez recently sat Upton due to a sore hand and he had thumb issues last season.  Could that explain it?  Another contributor mentioned witnessing a particularly rough swing-and-miss from April.  Players can play through oblique strains, but it will affect the player's abilities in the box to some degree.  Andruw Jones had quite a few issues himself with hurting his sides on his corkscrew swings.

If Upton is hurt, sitting through the All-Star Break would be advisable.  He had parlayed a huge start into a prime position for a spot in the All-Star Game, though it seemed likely that spot would fall before the final voting results were announced.  Regardless, he ought to stay home and rest so that he could hopefully jump-start the rest of his season.

Course, that is under the pretense that he actually is hurt.  It could all be mechanical.