The week before Christmas, I conducted an investigation into the Giants’ strange sinker-ballers. Logan Webb and Alex Wood enjoyed spectacular years, and they both did it using sinkers they released from a low starting point, which created a unique look for batters.

You probably didn’t read that article, and that’s okay. It was the peak of the holiday season. You were likely out in the world like me – seeing family, drinking eggnog-flavored coffee beverages, and generally making up for last year. My consumption of baseball media went way down, and I do this for a living.

As a self-interested person, I suggest you go back and read that article. I thought it was pretty good! More importantly, though, I’ve been doing more research into what the heck a “flat sinker” even is. The concept just doesn’t fit into my brain, and when that happens, I like to hit myself over the head with data until something clicks. So today, please enjoy some random things I’ve researched while trying to understand why in the world “flat” (approach angle) and “sinker” (pitch type) coexist. Read the rest of this entry »

For nearly a decade, you couldn’t go a week in the offseason without seeing an article about the American League’s dominance over the National League in interleague play. I know – I was already a rabid consumer of Hot Online Baseball Takes™ at the time and drove myself to distraction trying to find reasons to believe or disbelieve it. But it was interesting! The AL and NL split World Series roughly down the middle, but the AL kept winning interleague play and World Series games. Was it just a better league?

In 2018 and ’19, the trend flipped. The NL won the interleague season series in both of those years, which marked their first victories in that theoretical season-long series since 2002 and ’03. It had been quite a while, in other words.

By 2020, “who’s winning the interleague series” didn’t feel as interesting, and the unique pandemic-shortened schedule drove that point home even more surely. Due to geographically-divided schedules, there were nearly as many interleague games in 2020 as there were in ’19 (298 league-wide as compared to the standard 300 on the schedule every year since 2013), despite playing a 60-game season rather than 162. Not only that, but there wasn’t the usual rotation of opponents and rivalries. Instead, each division played its opposite-league counterpart. Read the rest of this entry »

Ah, sinkers. Wait three years, and the “smart” view of them will change. In the early 2010s, they were the coolest. A few years later, they were a laughingstock, a sure way to make your franchise seem old-fashioned. Between 2015 and 2019, the league abandoned sinkers (and two-seam fastballs, which I’m including in today’s analysis) en masse. In the former, pitchers threw 148,000 sinkers. By the latter, that number fell to 116,000. That trend is still ongoing; 2021 saw only 109,000 sinkers.

Despite the downward trend in usage, sinkers are cool again. When the league switched to Hawkeye tracking technology in 2020, the public could suddenly see the impact of seam-shifted wake, an effect that creates movement that previously wasn’t being measured. Pure transverse spin — like a backspinning four-seam fastball — is one way to create movement. Seam-shifted wake is another, and sinkers have it in spades, though they also generate plenty of movement from spin.

What does that word salad mean? Basically, sinkers drop and fade more than you would expect given the spin that pitchers impart on them. It’s not like sinkers started moving more in 2020 when cameras caught this effect, but quantifying something makes it easier to look for and teach.
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After a quiet 2020 offseason, and in advance of the ongoing lockout, the early 2021-22 free agency period saw a sudden burst of activity. Teams shelled out more than $1.5 billion in new contracts, a record-breaking pace. Not only did they act earlier in the winter than we’re used to, they also spent far more than last offseason. Is free agency fixed? We’ll need to dive into the data to find out.

See, “how much money was spent on free agents” is an inexact measure of teams’ spending appetites. Imagine an offseason where, due to strategic contract extensions and a wildly immoral use of cloning technology, the only players on the free agent market are 37 versions of Alcides Escobar and 25 copies of Jordan Lyles. Free agency spending would crater, and it would be hard to blame teams for it. It’s not as though you have to give the best player on the market a $300 million deal; contracts are, obviously enough, affected by the caliber of player signing the contract.

Rather than come up with some new form of analysis, I decided to use a methodology advanced by former FanGraphs writer Craig Edwards. The idea is straightforward: take players projected for 2 or more WAR by Steamer in the upcoming season, apply a naive adjustment for aging, and project how much WAR each free agent will accrue over the life of their contract. Like Craig, I applied some discounting for playing time projections. That lets us create expected $/WAR numbers for each year’s free agency class:

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At the end of October, I wrote about the alterations José Urquidy made to his arsenal during the postseason, trying to estimate how much better or worse his pitches might have been given their velocity and movement changes. In that piece, I briefly touched on raw movement changes but mostly relied upon the vertical and horizontal approach angles (along with location and release point changes) of Urquidy’s pitches to try to fully encapsulate their movement. While the concept and value of vertical approach angle is rather intuitive, I figured it would be useful to go into horizontal approach angle here today and have fun with a little exercise.

This post is inspired in part by all that we have been able to grasp in the public sphere when it comes to vertical approach angle. Measuring the up-down angle of a pitch as it enters the zone is largely derived from the vertical movement measures we’re so accustomed to. Steep vertical movement on breaking pitches and “rising” four-seam fastballs in the upper parts of the zone have been coveted for a while now because we know those pitches are associated with whiffs and therefore success. Much less can be intuited by simply looking at the pitches with above average horizontal movement. Read the rest of this entry »

With last week’s lockout of the players by ownership, the league has frozen all transactions for the foreseeable future. That’s bad news — but it also makes this a good time to take a snapshot of team payrolls, because there are no new deals coming down the pipe to mess up the analysis midway through. As such, the following is an update on each team’s payroll as it stood at the start of the lockout. Here are our team-by-team RosterResource projections:

A few notes, some of which will likely be familiar to you if you followed past versions of this exercise written by former FanGraphs writer Craig Edwards. The above data counts salaries for 2022, not average annual values. It includes estimates for arbitration, as well as estimated minimum salaries paid throughout the season; our payroll pages currently use the 2021 league minimum, but that number could change in the upcoming CBA. The numbers don’t include incentive bonuses, or a few specific CBA wrinkles, such as the approximately $2 million that teams pay to players who aren’t in the majors but are on the 40-man roster or the roughly $16 million per team spent on player benefits. They also don’t include as-yet-unsigned free agents, naturally.

The Mets’ recent signing spree, combined with the Dodgers’ losses in free agency, has seen the two teams change places at the top of the payroll standings (somewhat surprisingly, the Mets finished as the second-highest spenders in 2021). All told, there are three teams (the Mets, Dodgers and Yankees) that are currently projected for more than $200 million in player salaries in 2022, the same number (and the same teams) as last year. Meanwhile, there are two teams (the Pirates and the Guardians) with projected payrolls below $50 million, one more than last year, and neither of those teams is likely to make meaningful free agent signings when transactions resume. Read the rest of this entry »

MLB’s plan to de-juice the baseball this year seems to have worked. Home runs were down in 2021 compared to the last couple of seasons, though not by so much as to warrant a complete shift in the game’s current offensive paradigm. Instead, run scoring — which remains heavily concentrated around home runs — decreased overall. Non-pitchers hit just .247/.321/.418 this year, representing the second-lowest batting average in the live ball era (1920-present and excluding 2020) but the fourth-highest isolated power.

In slightly de-juicing the baseball, MLB erased some home runs. But as we can see in the sudden drop in batting average, which is down nine points for non-pitchers compared to 2019, shaving off homers didn’t result in other types of hits. As I wrote in my second of two pieces analyzing early 2021 home run trends, these lost homers mostly just became outs. That explains the significant reduction in overall offense, even as the league-wide home run total remained quite high in the context of baseball history.

With the season now officially complete, it’s time to revisit some of those early trends to get a final estimation of the effect of MLB’s de-juicing. Of course, there is a significant, potentially confounding, variable that makes 2021 different from other full seasons and complicates our analysis: the midseason enforcement against the use of sticky stuff. I will try to account for that here, though it probably deserves its own standalone examination. Read the rest of this entry »

Every season, we brace ourselves for the inevitable decline of baseball’s stars of yesteryear. Unfortunately, we’re all getting older, and despite their rare talents and athleticism, major leaguers eventually lose production. But while each individual has their own rate of decline, generally speaking, we know a fair amount about how age affects hitters’ abilities: A typical player peaks around age 26 and gradually declines afterward in what we know as the age curve. For those fortunate enough to stick around into their late 30s. that decline becomes quite sharp.

The basis for the age curve is the difference between a player’s performance across two different seasons. The choice metric for hitters tends to be wRC+, because it’s adjusted for league average and should be less impacted by league-wide trends and fluctuations from one season to the next. The chart below shows an age curve for players using data from the last 10 seasons, preceding 2021:

The shape of the age curve makes intuitive sense, for two reasons. The obvious one is that the primary skills needed to succeed in baseball (eyesight, strength, agility, etc.) decline as the human body gets older. Another, however, is that players only remain at the big league level if they’re successful. Whether it be due to injury, a slump, or even a little bad luck, a decrease in a hitter’s performance is an inevitability before they decide to retire (or the decision is made for them). Read the rest of this entry »

The playoffs feature the best teams, with the best hitters squaring off against the pitchers with the best stuff. The stakes and the quality of the competition force teams to respond to fluctuations in leverage more quickly than they would in the regular season. This response makes sense: every change in win probability has an outsized effect on championship probability, so major league clubs act accordingly.

In his dissection of Kevin Cash’s decision to pull Blake Snell in the sixth inning of Game Six of the 2020 World Series, Ben Lindbergh pointed out that starting pitchers leave playoff games earlier than regular season contests, with relief pitchers now throwing the majority of playoff innings. Lindbergh also noted that more playoff starters threw 3 1/3 innings or fewer in 2020 than went at least six, a product of teams’ acceptance of the third time through the order penalty. The third time through the order penalty is real, especially for starters who lack deep repertoires. Removing starters after they turn the lineup over once or twice in favor of a high-octane bullpen arm throwing 97 mph with a slider gives the pitching team a better chance of recording an out in situations where the outcome of the game hangs in the balance.

With starters aware that they are on a short leash and likely won’t see a hitter more than once or twice, I figured it was worth looking at how pitch usage changes in the postseason. I pulled every pitcher who threw at least 50 pitches in both the regular season and the playoffs from 2015-20. I calculated each pitcher’s pitch usage in the regular season and playoffs separately and took the differences in pitch usage for each pitch. My hypothesis was that hurlers who feature a bevy of different pitches would lean more on their more trusted offerings knowing they likely won’t be asked to go deep into the game and will be pulled at the first sign of any trouble. Similarly, I thought that pitchers who employ a limited arsenal would trust their favorite pitch with the increased pressure of getting their clubs back to the dugout without allowing runs. Read the rest of this entry »

Yesterday, I tested how well our playoff odds have predicted eventual playoff teams. Today, I’m going to slice the data a few more ways to get a more robust look at what our odds do well, and where they have fewer advantages over other models. It will be number- and picture-heavy, word-light. Without further ado, let’s get started.

A discussion with Tom Tango got me wondering about why our Depth Charts-based odds do so well early in the season relative to other systems. Their advantage is particularly strong at the beginning of the season and fades as the year goes on. For all charts in the article that are based on days into a season, I’ve excluded the 2020 season for obvious reasons. Here are the mean average errors for each of the three systems over the first 60 days of the season:

What’s driving that early outperformance? In essence, it comes down to one thing: the projection-based model is willing to give teams high or low probabilities of making the postseason right away. Our season-to-date stats mode is hesitant to do that, and the coin flip mode obviously can’t do it. Take a look at the percentage of teams that each system moves to the extremes of the distribution — either less than 5% or more than 95% to make the playoffs — by day of season:

Why does this matter? If you’re judging based on mean absolute error, making extreme predictions that turn out to be right is a huge tailwind. If you predict something as 50% likely, you’ll have an error of 0.5 no matter what. The further you predict from the center of the distribution, the more chance you have to reduce your error.

Of course, that only works if you get it right. If you simply randomly predicted either 5% or 95% chances without any information about the teams involved, you’d do just as poorly as predicting 50% for everything. Making extreme picks when you have information that suggests they’re likely to be right is the name of the game. Read the rest of this entry »