Young Players Are Leading the Rise in Three True Outcomes

The defining characteristic of that period in baseball now known as the PED Era isn’t particularly hard to identify: it was power. Home-run totals increased across the game. The long-standing single-season home-run record was broken multiple times in a few years. And, of course, drug testing ultimately revealed that many players were using steroids and other PEDs specifically to aid their physical strength.

Attempting to find a similarly distinctive trend for the decade-plus since testing began isn’t as easy. For a while, the rise of the strikeout seemed to be a candidate. A combination of increased velocity, better relievers, and a bigger strike zone has caused strikeout rates to increase dramatically in recent seasons.

Over the last couple years, though, we’ve also seen another big rise in homers — a product, it seems, both of a fly-ball revolution and potentially juiced ball. We’ve also witnessed the aforementioned growth of the strike zone begin to stagnate, perhaps even to reverse.

The combination of the strikeouts with the homers over the last few years has led to its own sort of trend: an emergence of hitters who record a lot of strikeouts, walks, and homers — each of the three true outcomes, in other words — without actually hitting the ball in play all that often.

The players responsible for this development are the sort who swing and miss frequently while refusing to offer at pitches on which they’re unable to do damage. To get a sense of who I mean, here’s a list of the top-10 players this season by percentage of plays ending in one of the three true outcomes.

That’s a pretty representative collection of the sort of hitter I’m talking about. Not only are these guys refusing to hit balls in play, they’re being rewarded for it: all but two have recorded distinctly above-average batting lines.

And this group of 10 is representative of a larger trend across the league. Consider how TTO% has changed in the 20-plus years since the strike.

That’s a pretty big increase over the past few seasons (even as I direct you to note that y-axis doesn’t begin at zero). The TTO% from 2015 to 2017 has gone up 2.7 percentage points, from 30.7% to 33.4%. Some of that (about a quarter) is attributable to a rise in home runs. Walks and strikeouts, however, account for the rest of the difference — and, in a time when the league and its fans are asking questions about the sort of game they’d like to see, that might be regarded as a problem. Generally speaking, action on the field of play is a positive thing. Walks and strikeouts are antithetical to that.

I should note: there’s a relationship between high TTO% and offensive output. Home runs and walks both represent positive outcomes for batters. And that’s sort of the problem: players are incentivized to pursue a three-true-outcomes approach. Obviously, there are other hitters who excel by putting the ball in play. Overall, though, homering and walking, even if it means striking out more often, is a pretty strong strategy.

Now, you might think the players on the extreme end — your Aaron Judges and Joey Gallos and Eric Thameses — are the ones most responsible for the increase in three true outcomes over the last few years. That’s not necessarily true.

I looked at all individual qualified seasons from 2015 to 2017 and separated them into three categories based on TTO — either high, medium, or low — and looked at the changes over the duration of that period.

The results:

The high TTO players saw the biggest increase from 2015 to 2017, but that increase wasn’t dramatic when compared to the players on the other end of the spectrum. All three groups saw pretty significant increases. In the PED era, Mark McGwire and Barry Bonds recorded very conspicuous home-run totals, but the light-hitting players increased their power outputs during this time, as well. So it is with the three true outcomes. We’re seeing increases across the board, although the offensive production isn’t really showing big changes from any group.

Players can move in and out of the groups above depending on their performance in any given year, so I thought it might be a good idea to check on a single group of players who qualified in each season from 2015 to 2017. Sixty-three players fit that bill and here’s how those players changed compared to the league around them.

Players who qualified in all three seasons changed a lot less than the rest of the league. While there are certainly players from all age groups in this group, we are dealing with a subset of players that includes a lot of veterans. The groups above accounted for around 20% of all plate appearances in the majors during those years. Perhaps checking by age might reveal some sort of pattern when it comes to the increase in three true outcomes. Here’s what happened when I looked at players 27 and under by TTO.

It would appear that young players might be driving these changes a bit. Here are a few more relevant stats from that age group in terms of the percentage of plate appearances they’re receiving and their home-run rates.

Young players are driving the increase in three true outcomes in two ways. First, young players’ percentage of plate appearances that end in one of three three true outcomes is increasing at a higher rate than the rest of the league. Second, these same young players are seeing a significant increase in the number of plate appearances they’re receiving. Their home runs are outpacing those increases in terms of their overall share, but as we can see from the final column, the homers per plate appearance isn’t that large compared to the rest of the league on the whole and doesn’t come close to explaining the increase in three true outcomes. Why this is happening is a question for another day, but in terms of who is responsible for the increase in three true outcomes, it’s those damn kids.