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)?
Every year it seems a handful of players go on a September heater and change the destiny of their fantasy teams. Some of those players are flashes-in-the-pan, but some have staying power. Last year’s class of league winners did produce some solid breakouts, with Ben Rice leading the charge, and Iván Herrera and Daylen Lile not far behind. For players like Michael Busch and Jo Adell, strong seasons were capped off by big power outputs to end the year, helping us believe in their power carrying over to this season.
Our Lesser-Known (at the time) September Heroes, 2025
Plenty of hitters increased their barrel rate per plate appearance by 3 points or more since July 1, even if we limit ourselves to hitters with 50+ plate appearances. Unsurprisingly, these hitters with higher barrel rates have improved their 90th-percentile exit velocity (EV90) and expected batting average (xBA).
The chart below the barrel rate difference in the rightmost column. The first three columns are numbers since July 1; the next three are the numbers from before July.
Stolen bases is one of the easier categories to quickly ascend. In the past, all you had to do was acquire Juan Pierre, Dee Strange-Gordon, or Michael Bourn, among many similar hitters, and within weeks, likely gained a couple of stolen base points. In general, we have far fewer of these types of hitters nowadays, but there are certainly two that stand out this year, both of whom will be discussed below. Let’s now review nine names to either consider acquiring or watch for an opportunity.
Every Monday, this column will break down the most popular waiver wire and free agent acquisitions from the weekend. I dig into the top adds on the ever-popular Fantrax and in the NFBC Online Championship (OC), a national mid-stakes contest with 240 total leagues of 12 and a six-figure grand prize. Reviewing player adds between the two should provide us with a well-rounded perspective and barometer of the fantasy baseball marketplace.
The callups keep rolling in and deep leaguers need to constantly pay attention. Since last week, five more have now been handing an everyday role or the potential for one. Let’s dive in.
• With all the injuries to the team (Kurtz, Langeliers, Rooker, Soderstrom, Kuroda-Grauer, Clarke), this lineup is pathetic. Lawrence Butler couldn’t make the lineup earlier in the year, and now he’s batting cleanup. Read the rest of this entry »
BREAKING: The Seattle Mariners plan to call up left-hander Kade Anderson, the top pitching prospect in baseball, to start Saturday, sources tell ESPN. Anderson, the third pick in the 2025 draft, has a 1.06 ERA over 93.1 innings with 135 strikeouts, 13 walks and 47 hits allowed.