While there have been a number of compelling storylines surrounding the 2020 season, none have been as fun as the San Diego Padres. Built around what appears to be a generational talent in Fernando Tatis Jr, the Padres were one of the most active teams at the deadline. Their incredibly talented offense has helped to push them into playoff contention and their additions seem to be targeted at filling holes. However, despite all of their success, their budding ace Chris Paddack has struggled mightily in 2020. After finishing second in the Rookie Of The Year vote, Paddack appeared destined to be a frontline starter for years to come. Yet so far in 2020, he has struggled mightily seeing his ERA jump to 4.4. Let’s take a look at his location data to see if there is an explanation for his struggles.

Chris Paddack

As has become customary for me, the first thing I like to look at with pitchers is a change in pitch mix. Paddack however, seems to have no such change. He heavily features two pitches, a fastball and a devastating change-up. He also mixes in enough curves to keep hitters honest. However, there are no major differences in usage. Yet, what jumps off the page looking at his Statcast numbers is how hard is fastball is being hit. After allowing a sub .300 xwOBA in 2019 with the fastball, that number has jumped to well over .400 according to Baseball Savant. The change-up seems to be getting similar results so the question is, what has changed?

With something like this, my first check is always how the location plot looks. As we can see with Paddack he does not appear to be locating the pitch horribly. While there is a decent amount of pitches overlapping with dark red portions of the plots, fastballs in general get hit pretty hard. The averages show this as well. Paddack’s location-based xwOBA is middle of the pack for all pitchers with at least 200 fastballs thrown. Actually his xWhiff is 10th best in all of baseball in that same sample. So, it appears that the location of the pitch does not appear to be the issue.

So what gives? How did this great fastball from a year ago turn into an extremely hittable pitch? Well the answer may also appear on his Savant page.

The line we care about here is the red line. His fastball last season average two inches more vertical movement than average and this season is also moving less than the average fastball. These averages come from using pitches with similar velocities and release/extension. This is a massive change. Vertical movement on the fastball has become all the rage in recent seasons for good reason. It is one of the most important factors in swinging strike rates for fastballs. Looking into some quick surface numbers there does not appear to be a difference in spin rate. However, there is a small difference in release point compared to 2019. This leads to believe he may not be getting on top of the fastball as well as he did last year leading to a small change in the spin profile. According to Brooks Baseball, there is a small spin axis change that could be accounting for this. Overall, this is a very minor difference but it shows how thin the margin for error is with fastballs. Even seemingly elite ones can get hit hard is their underlying characteristics are modified slightly. I’ll be watching to see how Paddack’s vertical movement on the fastball changes the remainder of the season. If he does seem to get the vertical action back on his fastball I’ll be trying to buy him this offseason in Dynasty.

Stuff ERA Leaders