After looking at the White Sox Pitch Type Data for the returning starting pitchers, I decided to see if we could learn anything from the available pitch type data for our hitters. Well, just Josh Fields for now, but I plan on expanding that in the near future.
I've included Contact%, which isn't included in the THT article, but is available on all player pages at Baseball-Reference.com. I don't have the pitch-type data for contact rate, but you can see just how much trouble Fields has with the fastball through this method.
The ML average contact rate (for all pitches) is 80%; Fields checks in at 72% overall and 73.3% for our sample. The average Major Leaguer swings and misses (WHIFF%) at just 6% of the fastballs thrown; Fields is more than doubles that rate at 14%, and makes contact less than 70% of the time he moves the bat off his shoulder against fastballs.
I'd have to take a look at the data from other high-strikeout sluggers to form an opinion about whether Fields inability to hit pedestrian fastballs will keep him from becoming a major leaguer. But right now, I think we can at least back up what we all saw over the course of the season with some hard data. Fields does not handle the fastball well at all.