What’s been causing Pfaadt’s struggles and what can he do to fix them?
Introduction
Entering this season, it felt like Brandon Pfaadt was primed for another breakout. After his stellar run in the 2023 postseason, he endured an up-and-down year in his first full season at the big league level. There were some highs – a 2.31 ERA in four starts in July – and some lows including a 6.51 ERA in 11 outings between August and September, albeit with some bad luck in the latter with a 3.67 FIP. Even though the overall picture for the year was more solid than spectacular, Pfaadt showed enough promise and durability to earn a vote of confidence from the front office in the form of a five-year extension before the year started. Curiously, the deal is structured to essentially buy out his remaining arbitration years with options for his first two seasons of free agency (one club and one mutual respectively). Unfortunately, that vote of confidence has not translated into much success to this point in the season. After a hot start to the season when he worked to a 2.78 ERA and 1.12 WHIP in his first six starts, it’s been nothing but misery since then as he’s posted a 7.25 ERA and a 1.60 WHIP over the next 11. If we take out the nightmare he endured against the Nationals when he gave up eight runs and failed to get a single out, it improves the picture but only slightly to a 5.84 ERA. So with him set to take the mound tonight in the series finale against the Giants, I thought it might be a good time to take a deeper dive into what’s been causing those struggles this year – and what can be done to fix it.
Struggles
Frustratingly, there isn’t a single cause for the poor play from Pfaadt and that makes it that much more difficult to diagnose the fixes. One look at his Baseball Savant page shows way too much blue for my comfort – especially the hard hit percentage and whiff percentage which basically rank at the bottom of the league. The arsenal hasn’t dramatically changed from last year either. The 2020-draftee mostly relies on his four-seam fastball, sweeper, and sinker for around 73% of his pitches, none of which has changed much from last year when those three comprised 80% of his arsenal. If we look at his individual pitches, the curveball stands out in all the worst ways as his weakest pitch in his arsenal and one of the worst curveballs in the league. The only pitch that’s been above average to this point has been his sinker and even that carries a 65% hard hit rate.
But what’s been the most concerning to me has been the regression of his fastball year-over-year from a weapon that helped set up his secondary pitches to a subpar pitch that’s a borderline liability. Last year, Pfaadt’s fastball generated a 22% whiff rate and he struck out batters 18% of the time he threw them one. It wasn’t necessarily an elite fastball, but like nearly all pitchers, Pfaadt depends on his fastball to set up any non-fastball pitch. This year, those same numbers for his fastball are 18% and 14% respectively, which has translated to an elevation of a worse hard hit rate and an expected slugging to a staggering .707 so far.
Successes
I don’t want to paint an unnecessarily negative picture of where Pfaadt stands. He’s demonstrated plenty of success so far in his career – as recently as this June he looked like a Cy Young candidate. And I think at least some of his struggles this year can be chalked up to poor luck as evidenced by a FIP that’s half a run lower than his actual ERA (4.89 versus 5.38). We should also keep in mind that he’s still in just his second full season at the major league level and that player development is rarely linear. And unlike his teammate at the top of the rotation, Zac Gallen, Pfaadt has been excellent at not walking batters, which undoubtedly has kept his FIP low and allowed him to work deeper into games. In fact, he’s had just four starts where he hasn’t completed five innings and has completed six innings in almost half of his starts this season (eight including tonight out of 18 starts). That level of stability was crucial last year and has proved similarly important this year given the depleted state of the D-Backs’ bullpen. But baseball is a game of adjustments and Pfaadt is in desperate need of a major adjustment to return to his early-season form if he is going to find any kind of consistency.