Midseason, I charted the rookie crop of pitchers using a z-composite score. As the first full season for many of these pitchers wraps up, let’s come back to them to see how they fared and what this means for fantasy value moving into 2027.
Entering his contract year, Freddy Peralta was one of the biggest offseason moves, coming to the Mets from Milwaukee as a top-20 starting pitcher in fantasy ADP. For Peralta, the Mets, and anyone who drafted New York’s prospective ace this season, 2026 is a year that has not gone as planned. But following a fresh start in Florida, it seems as if Peralta is back on track, at least for now. We will look at this rollercoaster season for Freddy Peralta, what this means for his fantasy value in 2027, and what he can learn from both his time in New York and Tampa Bay.
Using Statcast data, we can track which of the four aspects of a hitter’s batting stance moved and by how much across each month of the season. In this piece, I wanted to go a step further with some of the names from part one and layer in bat tracking data and batted ball tendencies to see whether the stance changes translated into a measurable swing change.
Over the course of a 162-game season, many casual fans may be surprised by how much a hitter might adjust their stance and setup. Often, the assumption is that once any athlete reaches the pinnacle of their sport, there is resistance to change, particularly mid-season, and any major mechanical changes are reserved for the off-season. But it turns out hitters are constantly tinkering with parts of their stance, particularly when looking to find some form.
As we move on to the final stages of this fantasy season, one more splits chart could be beneficial for those looking for streaming options in a playoff run. This chart plots xwOBA vs left-handed pitching (LHP) and right-handed pitching (RHP) on each axis, with filter options for which teams to target depending on their split, with the biggest gap differentials also included. This is done using handedness split data since the break, which now has a big enough sample in its own right while capturing recent form that full-season data would dilute. This piece will identify which handedness offenses struggle with and also look at probable starters up until September 19th, for specific matchups for both pitchers and offenses. Bear in mind this is overall offensive production; there will be specific hitters within lineups that may do well against a certain handedness despite the overall offensive struggles, and vice versa.
OpenCommand, introduced by Doyoung-Tom Kim, is an absolutely incredible open-source dataset that offers a new way to track pitch locations based on target-miss distance, how far a pitch landed from where the pitcher was actually trying to put it, estimated from the catcher’s setup and camera tracking. Without going too much into detail about the workings of OpenCommand, I would highly recommend checking out his work and the great lengths he went to account for camera angles, plate depth, etc.
Feels like a starting pitcher is hitting the IL every day. Or is that just on my fantasy team? As I scoured the waiver wire for options to just get me some innings, I wanted to try to at least maintain some kind of floor.
When looking at pitchers outside of your top rostered starters, it can be a minefield; these are pitchers not picked up for a reason. The problem that can be prevalent is that these pitchers are susceptible to blow-up innings that quickly crater decent starts into nightmare starts. Often this takes place on the third time through the lineup.
Induced vertical break (IVB) is a measure of how much vertical movement or ride a fastball has. It can be an important factor in determining the shape of a pitcher’s fastball, and some pitchers are much more reliant on it than others. It can be the difference between six to seven innings and getting pulled after four and a third. As we get to the final weeks of the season, movement and ride on a pitcher’s fastball can begin to degrade after the wear and tear of the season. This piece will look at what kind of pitchers are reliant on IVB for success, which pitchers have been most impacted by the wear and tear of the season, and who is still able to maintain vertical movement in the final stages of the season. Which pitchers’ four-seams actually depend on IVB, and where is that IVB heading right now?
Building on my piece a couple of weeks ago on the normalization of Z-O, it felt like there was a lot more left on the bone in terms of finding out if permanent changes to a hitter’s approach are possible, and if so, how long does it take for a new baseline to be established? In the first piece, we followed up on a discussion on X between redsoxstats and Eno Sarris, and introduced Z-O as a metric and the stickiness of it as a metric for plate discipline.
It seems to be, in general, once a hitter establishes his baseline, it is difficult to deviate too much away from that level throughout his career. This is due to how inherent a hitter’s approach is at the plate. Hitters have tendencies baked into their profile, and shifting from that is difficult. But this opened up a slew of further questions relating to how baselines are established: is it possible to establish a new baseline? If a hitter improves or declines from this baseline, how are we able to establish a new Z-O baseline (if at all)?
The tracker is back, running from now until the end of the season, so we can identify which teams have favorable groups of fixtures to stream for fantasy. At this stage of the fantasy season, identifying these stretches of games that have targetable hitters or pitchers could be the difference. I will link here the first iteration of the tracker that I made through the end of August, with a more comprehensive breakdown, but the chart has a tab for both hitters and pitchers.