True Outcomes and Players Through Time

Most readers understand that the phrase Three True Outcomes (TTO) refers to walks, strike outs and home runs. In an August 2000 article at Baseball Prospectus, Rany Jazayerli noted that these outcomes are “true” in the sense that they are largely independent of all things — outside that mano-a-mano moment between the batter and the pitcher:

Together, the Three True Outcomes distill the game to its essence, the battle of pitcher against hitter, free from the distractions of the defense, the distortion of foot speed or the corruption of managerial tactics like the bunt and his wicked brother, the hit-and-run.

None of the three true outcomes are significantly impacted by what happens outside the batters box*. Therefore, players with a higher percentage of plate appearances that end in TTOs have their fate largely decided at the plate. The poster child for the TTO? Rob Deer. His career TTO percentage ((HR+SO+BB)/(PA)) was 49.7%.

I thought it’d be interesting to look at how TTO players have evolved over time and what accounts for their successes and failures.

This visual shows how the percentage of full-time position players classified as TTO has changed over time. The white bars are the percentage of TTO players in a given season compared to other full time players (>= 500 PAs). The lines illustrate the trends in league-wide home run, strikeout and walk rates per plate appearance.

And who’s that lone player in 1920? He’s Babe Ruth. After that Ruth season, we don’t see any TTO players again until Mickey Mantle, in 1961. After the Mantle year there are only a few TTO players sprinkled in here and there. But in 1986 we see a string of 26 uninterrupted seasons — with the exception of 1994 — with at least one full- time player who reached the TTO plateau.

In 2008, Major League Baseball saw the most TTO players (seven) and the highest-ever percentage of TTO players (5%).

If we raise the qualifying bar a bit — to home runs, strikeouts and walks greater than or equal to 50% of all plate appearances — we get the following:

I wanted to go back the Ruth era, so I didn’t exclude intentional walks because that data was not available until 1955. Either way, though, it’s pretty clear what drove the rise of TTO players: home runs and strikeouts.

Between 1920 and 2011, league-wide strikeouts per plate appearance increased 139%. Home runs? A whopping 258%. Walks, though, only increased 12%. The degree to which batters walked actually peaked back in the late-1940s. Strikeout and home run rates peaked much later.

As far as individual players go, the tables below show the number of times players qualified with TTO seasons at both the 50% and 45% levels (sorted on 45%, top 20 only):

Player (with iBB) 50% 45%
Jim Thome 3 12
Adam Dunn 3 8
Rob Deer 3 6
Carlos Pena 1 5
Mark McGwire 3 4
Mark Reynolds 2 4
Barry Bonds 2 4
Jim Edmonds 0 4
Jack Cust 2 3
Jack Clark 2 3
Ryan Howard 1 3
Mickey Tettleton 1 2
Jose Canseco 0 2
Mike Schmidt 0 2
Mark Bellhorn 0 2
Danny Tartabull 0 2
Mickey Mantle 0 2
Reggie Jackson 0 2
Jay Buhner 1 1
Dave Nicholson 1 1

While Rob Deer is typically known as the embodiment of TTO, Jim Thome has a legitimate claim to the throne, too. Thome had three seasons with a TTO above 50% and 12 seasons with a TTO above 45%.

If we remove intentional walks, Thome still looks good:

Player (w/out iBB) 50% 45%
Jim Thome 2 10
Adam Dunn 1 8
Rob Deer 3 6
Carlos Pena 0 5
Mark McGwire 1 4
Mark Reynolds 2 4
Jim Edmonds 0 3
Jack Cust 2 3
Jack Clark 1 3
Ryan Howard 1 3
Mickey Tettleton 1 2
Mike Schmidt 0 2
Mark Bellhorn 0 2
Barry Bonds 0 1
Jose Canseco 0 1
Jay Buhner 1 1
Dave Nicholson 1 1
Jimmy Wynn 0 1
Cecil Fielder 0 1
Gorman Thomas 0 1

Deer might have one more season over 50% than Thome, but Thome still has 10 seasons above 45%, which is four more than Deer and  two more than Adam Dunn. Not only that, but Thome was much more productive than Deer. Thome has a career wRC+ of 145, while Deer only managed to be 9% better than league average. Now, a 109 wRC+ for your career is nothing to sneeze at, but Thome has clearly been the better overall hitter.

So while Deer might be the poster-child for TTO, it’s safe to say that Thome — with his overall production and edge in true outcome seasons— is the greatest TTO hitter of all time.


*Of course, there is the occasional inside the park home run, which relies on batter speed, hit location, and defense. There is also the rare play where an outfielder makes a play on a fly ball and aids the ball over the fence that otherwise would have remained in the park. But, by and large, these outcomes are independent of events and variables outside of the batter’s box.

Bill leads Predictive Modeling and Data Science consulting at Gallup. In his free time, he writes for The Hardball Times, speaks about baseball research and analytics, has consulted for a Major League Baseball team, and has appeared on MLB Network's Clubhouse Confidential as well as several MLB-produced documentaries. He is also the creator of the baseballr package for the R programming language. Along with Jeff Zimmerman, he won the 2013 SABR Analytics Research Award for Contemporary Analysis. Follow him on Twitter @BillPetti.

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10 years ago

Of course, 2 of the outcomes (Ks & BB) are only “True” if you assume the catcher has no effect on the ability to get strikes & balls…which we now know isn’t correct.

10 years ago
Reply to  Bill Petti

Pretty much. For any one pitcher, the WAR shift if probably .1 going from the worst to the best pitcher. But it’s still there.

At the other end, some ground balls are “truer” than others…notably the ones that are caused by a consistent ability to generate weak contact, making them easier to corral & lowering a pitcher’s BABIP.

And if we really want to get into it, HR are a product of the pitcher, hitter & park.

But now I’m just nitpicking. It would be interesting to lay these things out on a scale, and see how independent they really are.