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We’re about a third of the way into the COVID MLB season and batting average (BA) is down. BA is .241 after averaging .252 the past three seasons. A close cousin to BA, Batting Average on Balls in Play (BABIP), has been between .295-.300 for years but in 2020, BABIP is .285.
In addition to BA and BABIP, other stats have been used to assert a broader claim that offense overall has declined. For instance, OPS (on-base plus slugging) has been cited to imply a drop in power in 2020. Indeed, OPS is down from an average of .745 the previous three seasons to .733. But to imply that stat necessarily says anything about power is sloppy. Both halves of the formula for OPS — OBP and SLG — include batting average. So the decline in OPS merely reflects (twice) the decline in BA, nothing more.
So the mystery we’re trying to solve is about fewer base hits.
This question has spawned many theories to explain it. And I mean many. The pitchers are ahead of the batters and that suppresses the quality of contact, the ball is less lively, fans and their white shirts aren’t in the stadium to distract fielders, hitters can’t look at video between at-bats, pitchers aren’t facing batters a third time as much, hitters are too focused on launch angle and pop up more, improved pitch framing by catchers has created a bigger strike zone, the greater use of defensive shifts, a few good hitters have opted out.
As you graze that Golden Corral of explanations, consider one simple fact that undermines almost all of them …
The decline in hitting has been from the left side only. Right-handed batters are doing just fine.
Take a closer look at batting average. Historically, there is no difference in batting average between left-handed hitters and right-handed hitters (L/R):
- 2019 (.253/.252)
- 2018 (.248/.248)
- 2017 (.256/.254)
But this year
- 2020 (.228/.250)
You’d find the same with BABIP. From 2017-2019, the average BABIP was .298. For right-handed hitters BABIP was .298 and for lefties .297. No handedness difference. But in 2020, right-handed BABIP is .295 and left-handed BABIP is .271.
Power, as measured by xtra-base hits, or isolated power (ISO) has always been about the same for lefties and righties (L/R). 2019 (.184/.182)
- 2018 (.163/160)
- 2017 (.171/.171)
If anything, a slight edge for lefties. But this year (L/R):
- 2020 (.164/.182)
Note, for BA and ISO, right-handed hitting in 2020 is in line with the previous three seasons.
As a percentage basis of run creation, left-handed hitters usually contribute 4% more than right-handed hitters. Here are the wRC+ numbers for the past three seasons (L/R):
- 2019 (99/95)
- 2018 (99/95)
- 2017 (99/95)
That’s consistent. But look at the 2020 season as of today, lefties have lost about 16% in run creation relative to righties (L/R):
- 2020 (93/105)
Given that the decline in batting average, BABIP and isolated power is only on the left side, go back and evaluate that litany of explanations.
Virtually none can explain the drop in base hits because the effects would be seen on both sides of the plate. And we’ve shown they aren’t. To take one example, if the ball was de-juiced, we’d see equal drops with right-handed and left-handed batters. If the problem was not being able to look at video between at bats, it would be harming batters of both sides.
That doesn’t mean those theories aren’t legitimate causes for less offense. But offense overall isn’t down. Left-handed offense is down. Maybe right-handed hitters miss the video or don’t see pitchers a third time as often. But those factors are being offset by others pushing in the opposite direction.
One explanation that seems to withstand the handedness bias in declining offense is the greater use of shifts in defensive alignment. We’ll look at the evidence for and against that theory in the next post.
