When evaluating performance, we are prone to falling into pitfalls of confirmation bias. Whether it’s overlooking a fine defensive play by that player we don’t like or completely ignoring three or four horrid plate appearances from the guy we think is underachieving, avoiding confirmation bias is nearly impossible. Most opinions are founded in some sort of evidence, be it subjective or objective, thus it’s tough to just toss aside.
When examining Zach Plesac’s first three starts, it’s tough to avoid this pitfall. After spot starts by Cody Anderson and Adam Plutko, anything was going to be an improvement… so looking for immediate success from Plesac makes sense. To top it off, Plesac’s minor league profile was one to be adored, checking boxes like crazy — few walks, passable strikeout rates, and sheer success after a massive leap this year. Rooting for him to flourish at the MLB level is just… easy.
When diving into the data, it’s tough to find evidence to the contrary. We can stress over his fastballs that catch a lot of plate, as WFNY’s Mitchell Krall detailed here. We can worry about his rapid ascension from meager successes in previous minor league campaigns. We can stress about his inability to find enough out of his breaking pitches to get major league hitters out. But evidence indicates otherwise, and while these may be valid concerns, he has done nothing but live up to his 2019 minor league stat lines.
In his third start against the New York Yankees, he looked to be in grave danger. A few extra base hits allowed, including an Aaron Hicks homer, led to a 2-0 deficit after just three innings. This included a Houdini-like escape act to get out of a jam that was aided by an impressive Tyler Naquin cannon from the right field wall to cut down a runner at second base. Plesac stood his ground, though, and buckled down to keep the Yankees off the board for four more innings, setting up his first win of his short career.
Through 19 1/3 innings, Zach Plesac has only allowed four runs. His peripherals suggest he’s been a tad fortunate, highlighted by an unsustainably low 0.235 BABIP against and an unsustainably high 91.6% strand rate, but he has still been effective. Though he isn’t racking up strikeouts (14 in those 19+ innings), he’s limiting free passes and managing contact well enough to walk the line.
Plesac is using a fastball that sits 93-94 miles per hour and touches 96 to get ahead and slowing bats down with a plus changeup. The intriguing development in his short major league career, however, has been a slider that has generated positive results when called upon.
Though he’s only used it 42 times through three starts, it has been put in play 8 times… three ground balls, one line drive, and four lazy fly balls. He has managed contact at a mediocre clip with it, falling in at an around average opponent weighted on-base average mark. It has also been his best weapon for missing bats, as it has generated 8 swings and misses on those 42 offerings.
This is far from a conclusive sampling that the pitch is worthy of recognition, but more posited as a glimmer of hope that it can find that status eventually. It was also his primary vehicle for dodging the Yankees offense on Friday night.
Plesac upped his usage of the slider to attack the Yankees, throwing it 23 times. In these pitches, he induced two lazy fly balls, four whiffs, five called strikes, and six foul balls. It served as an effective median for his fastball that got touched up a bit and his changeup that cannot be too heavily relied upon.
In any consideration of the likelihood of Plesac’s future success as a starter, developing a serviceable slider or curve will be paramount. The early slider returns look to be serviceable, at the very least. When looking at actual results, which include pinning down two blue blood AL East offenses and a White Sox team that knocked around the rest of the Indians pitching staff, confirmation bias can be tossed aside — Zach Plesac looks the part.