The biggest reason to spend a huge contract on Dexter Fowler was his plate discipline. After one month of play, Fowler looks impatient.

You may remember that I had mixed feelings over the Dexter Fowler signing when it happened. I saw many possibilities for the upcoming season, and wasn’t sure what was most likely. But I didn’t see this coming.

I didn’t see any world in which Dexter Fowler increased his chase rate to 30 percent and his swing rate to 48 percent. Fowler’s calling card is his ability to take close pitches and draw walks. In April, we saw a different Dexter Fowler than what we are used to.

If you’re wondering why Fowler’s strikeout rate is up to 25 percent and why his walk rate is down to 8.4 percent, then you  should check out his plate discipline metrics.

The Cubs preached patience with Fowler at the plate, and it worked. Fowler swung just around 40 percent of the time, and chased around 20 percent of balls. Fowler had a career high 14.3 percent walk rate in 2016, while recording his highest wRC+.

Much of Fowler’s value is based on his ability to earn free passes and get on base. If he isn’t towards the top of the league in walk rate, then he won’t come close to returning $16 million per year. Fowler’s chase rate isn’t the only reason his performance is down this year, but it’s a big reason. The walks won’t come if Fowler keeps swinging when he shouldn’t.

Changeups

Pitch breakdowns are difficult to deal with early in the season because of small sample sizes. Nevertheless, I found some interesting trends regarding curveballs and changeups thrown at Fowler.

Since Fowler has logged less than 25 plate appearances as a right-handed batter this season, I will only be looking at when he is batting left-handed (and the pitcher is right-handed).

Prior to this season, Fowler whiffed on changeups 15.4 percent of the time, and on curveballs 8.2 percent of the time. In 2017, those numbers are up to 27.8 percent and 15.2 percent, respectively.

Pitchers are throwing their changeups and curveballs in a slightly different spot against Fowler this year. The results have produced a lot more whiffs. I will start with the changeup numbers.

                        
                                          Changeups vs. Fowler (2008-16)                                                                                                                                  Changeups vs. Fowler (2017)

The heat map on the left includes changeups thrown against Fowler from 2008-16. The heat map on the right is changeups in 2017 (both from Baseball Savant). Again, we are only looking at plate appearances where Fowler hit left-handed. In both cases, opposing pitchers are going low and away on Fowler.

But prior to this season, the goal still seemed to be to find the strike zone. In 2017, Fowler has seen more changeups outside the zone than he has inside it.

Throwing changeups in this region to Fowler is actually really smart. The following chart from Baseball Savant breaks down the pitch outcomes of each changeup thrown low and away and outside the strike zone to Fowler from 2008-16:

Fowler vs. Changeups, low and away (2008-16)

If a pitcher threw a changeup to Fowler in a certain spot outside the strike zone, he only had a 53 percent chance of the pitch being called a ball. For reference, less than 45 percent of pitches are actually thrown in the strike zone.

Pitchers were going for the low and outside corner against Fowler. Instead, they should have been going for off the low and outside corner. When the ball was over the plate towards the low and outside corner, Fowler had both a higher contact rate and a higher BABIP.

Fowler has a reputation as a very disciplined hitter. That is true when looking at other regions outside the strike zone. If we look at pitches outside the strike zone in any other region, Baseball Savant gives us this breakdown:

Fowler vs. Changeups, outside strike zone, not low and away (2008-16)

Fowler took nearly 80 percent of pitches that were off any other corner. His swing rate doubles if a pitcher goes down and away. Of the 36 changeups Fowler has seen this year, 21 were off the low and outside corner. Just a little more than one-third of the changeups he had seen prior to 2017 were in that region.

Perhaps pitchers are aiming for the plate and just missing. If they are going for locations off the plate, then the strategy seems to be working.

Curveballs

As mentioned at the beginning of the changeups section, Fowler is also struggling against curveballs this season. He is whiffing seven percent more often against curves, and some of the same trends apply. Here are the 2008-16 and 2017 heat maps for curveballs thrown against Fowler.

                 
                                            Curveballs vs. Fowler (2008-16)                                                                                                                                    Curveballs vs. Fowler (2017)

Instead, of going down and away, pitchers are just throwing their curveballs straight down. Of the 26 curveballs that Fowler has seen this year, 18 have been below the strike zone. Part of Fowler’s problem is that three of those 18 were called strikes. The other part is that Fowler swung and missed on four of them. 26 pitches is not nearly a large enough sample size to make any conclusions. However, Fowler has struggled in this area for his career.

For his career, Fowler has chased roughly 36 percent of pitches directly below the strike zone. Because of the way Baseball Savant breaks down pitch zones, I don’t know what his chase rate is specifically on curveballs in that area.

If we include anything outside or inside and also below the middle of the strike zone, then we get some idea of what happened. Fowler chased on 18 percent of those curveballs. That is low, but much greater than the five percent he had on curves up and away or up and in.

I am speculating a bit here, but I would guess that Fowler’s chase rate on curveballs directly below the zone is above 25 percent. 25 percent is above Fowler’s career chase rate of 22 percent on all pitches outside the strike zone.

If pitchers are targeting that section outside the zone, then Fowler’s chase rate will climb. Prior to 2017, pitchers threw about one-third of their curves directly below the zone to Fowler. In 2017, that ratio sits at 18 of 26. I wouldn’t quite say that pitchers have figured him out, but the Cardinals better hope that this trend does not continue.

Can it be fixed?

The best thing that Fowler can do is get ahead in the count. If he is having trouble laying off changeups down and away or low curveballs, then he has to put himself in a position where he doesn’t have to swing at offspeed or breaking pitches.

Outside of that, the Cardinals might need to help him with pitch recognition. Teams successfully train players to better recognize pitches all the time. The question is how effective it can be in season. Players make most of their adjustments in the offseason.

I don’t think the opponents’ emphasis on two pitches in two spots will doom Fowler. I think he can be alright even with teams targeting his weaknesses.

His chase rate probably won’t stay around 30 percent even if he doesn’t fix the problem and the early usage patterns are no fluke. I can’t explain a ten percent increase in chase rate with just the usage of two types of pitches.

As I mentioned in the beginning, plate discipline is not Fowler’s only problem right now, but it’s the most glaring one right now. Without his excellent plate discipline, Fowler might not be even an average MLB player.

The changeup and curveball problems need to be monitored by the Cardinals, but they also just need to make sure he is taking pitches more often. He won’t be that valuable if he is swinging six percent more often than he usually does. He certainly won’t be that valuable if he is swinging at balls ten percent more often.

All charts from Baseball Savant; charts accurate as of April 27

Photo Credit: Jeff Curry – USA TODAY Sports