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)?
In it, Bailey points out that Bennett intentionally throws his fastball up in the zone, using Bennett’s heat map to demonstrate frequency, his 115 Location+ to demonstrate efficacy, and Bailey’s own “Upstairs” metric, describing pitches thrown just above the strike zone, to reiterate the heatmap and emphasize Bennett’s intent relative to other pitchers, as Bennett leads all pitchers on percentage of Upstairs four-seamers this season.
Bailey went on to highlight Bennett’s lackluster four seam fastball in a vacuum, that is elevated by tunnelling with and playing off of his other pitches, particularly his sinker and changeup. All three of these pitches, Bailey points out, have positive run values for the rookie.
But what was most interesting to me was how Bailey concluded the video. He’d already proven Bennett throws with intent, locating his fastball well in relation to his offerings with better stuff to maximize his outcomes. But then he shifted to batted ball outcomes. Bennet’s sinker has elicited a 69% groundball rate and his fourseam a 26.7% IFFB%.
Bailey described himself as having “taken the pop up pill”, comparing infield pop ups to strikeouts in terms of utility to a pitcher. He showed us a list of pitchers with 70+ innings this season and both high GB% and IFFB%. Here’s that list.
Obviously, there’s some aces here and some low ERAs.
Bailey then shows Bennett’s league-leading Launch Angle Sweet Spot rate, which places him atop a list that includes Shohei Ohtani, Trevor McDonald, Janson Junk, and Framber Valdez. Not as impressive as the other list.
The premise seemed logical to me. As Bailey puts it, pitchers with good command throw pitches in locations that get a lot of strikes and a lot of suboptimal contact.
I was left wanting more. I wanted to know if Jake Bennett possesses a skill that historically is repeatable for pitchers. I think we assume we know “ground ball guys.” But is inducing infield pop ups a repeatable skill? And does it impact ERA in the same way a high ground ball rate does? I wanted to know if Bailey had shown why Bennett’s ERA was great this season, and if that “why” was worth turning into a strategy to predict future season ERA for other pitchers.
The crux of the fantasy season is looming, and decisions need to be made as we push to the playoffs. In one league currently, my shortstop position is in need of a jolt, and with a playoff spot already secured, time is running out to get aggressive and make a move. While Otto Lopez and Colson Montgomery have served me well for the majority of the season, the data is saying an aggressive move is required. Lopez, whose bat was running hot pre-All-Star break, has cooled, and even his .259 xwOBA says the bat isn’t good enough to wait on at this stage of the season. And Montgomery has no luck gap at all, with his results matching his .237 xwOBA.
Mandatory Credit: Christopher Hanewinckel-Imagn Images
The sweeper seems to be a pitch that has taken on a life of its own over the past few seasons. More horizontal movement generated by sacrificing velocity (generally). But maybe it doesn’t have to be that way. With an average velocity a couple ticks below the traditional slider (85-86 mph), a sweeper usually sits at 82 to 83 mph. But it has become a powerful weapon and a popular pitch to add to pitch arsenals for those looking for an added swing-and-miss pitch.
Discipline at the plate is often a huge driver for success over the course of a season. From a fantasy perspective, it can be difficult to utilize outside of just an overall gauge for a hitter’s success.
Following on from looking at those who have managed to increase the velocity on their four-seamer since the start of the season, it is now time to turn to those losing velocity. Some have not been so fortunate. Whether through wear and tear or potential injuries, these pitchers warrant serious monitoring and potential red flags as we move forward.
In the heat of summer, it is always interesting to track pitchers who have gained velocity and who are losing velocity, and what the impact is on their results. While velocity alone does not guarantee success, meaningful changes often coincide with adjustments in command, pitch quality, or overall effectiveness. Identifying those trends mid-season can be a very useful indicator to see if a pitcher could strengthen as the season goes on or decline. This piece will look at those hopefully strengthening in the summer.
Following on from the hitters chart, we now look at how pitchers have performed so far this year against their OOPSY rest-of-season (RoS) projections.
Continuing with the framework of the hitters’ piece, this will first look at those with projected ERA rises, then at those with projected ERA drops. Just as we identified BABIP and ISO as the major determining factors in the hitters’ RoS outlooks, we will identify a similar through line here: for pitchers, it is largely strand rate.
Earlier this week, I wrote about the importance of looking at a hitter’s performance on a per-game-started basis, particularly if you are in a daily lineups league. There are real risks to considering a hitter’s overall line without considering what they do when they start, and those risks can cut both ways. If you look at their rate stats and dream on the value of that .350 wOBA, you might miss that they lose plate appearances to pinch hitters, which might cost them 10% or more of their PA, even when they start.
If you look at their per-game stats, you might underrate a player’s power output or stolen base contribution because those numbers look bad overall, but they are actually on pace for 20/20 over 160 games. Today, we’ll account for those risks and look at a set of players whose overall and per-game performance might be hiding how good they have been on a per-game-started basis.
As we enter the heat of the post-All-Star break summer, it is a natural point for both reflection and action for our fantasy squads moving forward. This chart plots first-half wOBA against OOPSY’s rest-of-season projection (RoS); the pitching chart will be coming soon. It is a useful way to see the discrepancy between how some hitters have performed and what OOPSY expects for the rest of the season, and to discuss why regression is being projected, and in some cases why it isn’t, across the league.
