Dan Vogelbach is one of my favorite Cubs prospects. I love his bat and I love approach. Mostly, though, I loved his power. In 2011, he showed a taste, with a .542 SLG in 27 PA. In 2012, though, he exploded. His line was .322/.410/.641 over 283 PA. This was as a 19-year old who was promoted to A- halfway through the season. His body profiled as either a DH or a competitive eater, but that was a problem for down the line; as it was, he was a real offensive talent.
This year, it's been a different story. He was promoted to Kane County to start the year, and he struggled (for him). He put up .284/.364/.450 in just over 500 plate appearances. Those are fine numbers, and his K rate was still just 15.2%, a nice improvement from the previous season. However slugging had fallen almost 200 point from last year. That's a massive, massive difference, and makes Vogelbach a different caliber prospect entirely.
The news isn't all bad. Reports of his defense at first have went from "unplayable" to "bad." That's a far cry from perfect, but you can take a bad defensive 1B if a big stick is glued onto it. It's also not as if the power has evaporated completely; over his 2 stops and 556 PA, he still has 19 HR and 22 doubles.
Still, the season can't be viewed as anything other than a disappointment. Vogelbach has been praised for his great approach to hitting, and that hasn't changed. He still takes his walks (11.4% at KC, over 25% in a SSS at Daytona) and doesn't strikeout a whole lot.
So, where has the power gone? First, I looked at field dimensions. Memorial Stadium, where the Boise Hawks played, went 330-400-330. Those are short porches, but not uncommon in the minors. Kane County, on the other hand, is only 5 feet longer in the alleys at 335-400-335. I can't get park factor information for Boise, but KC is on the low side in the Midwest League, which is a typically difficult place to homer in general. Daytona is in even worse of a league for HR, but Daytona itself is a launching pad: 325 to right, 317 to left.
Another thing to consider is the fairly drastic change in body type. Vogelbach lost 40 pounds in between his draft and report to minor league camp, and another 15 or so pounds last offseason. That's hopefully all fat, but I can't help but wonder if he's just not as strong as he once was. It's not normal for someone to lose that much weight that quickly, and hopefully he gets to a place where he can find a little more strength. I think he could just be tired from remaking his body in the offseason.
One last thing to consider is a change in approach. Early on in the year, he REALLY cut down in his strikeouts. That is traditionally a warning sign that a power outage is soon to follow, because a player might just be trying to put a ball in play, and is generally ending at-bats earlier. This isn't always a bad thing, but in this case, that trade-off is NOT working for Dan. With power like his, pitchers WILL be afraid of him, which will lead to the walks and high pitch counts that you want to see.
Vogelbach is still a worthwhile prospect, but I'm not as high on him as I once was. Before the year started, I thought aggressive promotions could but him in Chicago at the tail end of 2014 (for call-ups). I'm not sure I see that anymore, with a 2015 timetable more likely. I'd like to see him repeat Daytona for the first half of next year, with a chance to go to Tennessee later on if things break right.