Say Goodbye to Steals and Hello to Fly Balls and Popups

While it’s going to be a while before we have a large enough sample size to properly evaluate hitters, it’s actually not too early to start acknowledging statistical trends on a leaguewide basis. So let’s dive into a series of ratios, comparing where we stand after just four days into the MLB season, with the March/April numbers going back to 2014.

Let’s begin with the state of the stolen base:

We could see from this trend that the number of plate appearances between stolen base attempts has gradually risen. Interestingly, it was stable in 2014 and 2015, then jumped in 2016, remained steady again, and has now skyrocketed so far this year. Fewer steals means that the guys who do continue to run will contribute a higher percentage of the stolen base pool than ever before. If you now only need 140 steals to win the category, a guy like Billy Hamilton or Dee Gordon may get you 40% of the way. On the other hand, if you now need 320 homers to win, even 50 dingers represents just about 16% of that total. It’s just a reminder that a steal is worth a heck of a lot more than a homer, ignoring the additional benefits of the homer (RBI, run, hit), of course.

We’re trending toward three true outcomes! I didn’t check out any pitcher metrics, though it would be interesting to see if league average fastball velocity is up again.

And now let’s check out the batted ball trends:

The fly ball revolution is in full effect! Batters are trading their grounders for everything else — literally, every other batted ball type is up. Ominously, IFFB% is up, which combined with the FB% spike, means there are more harmless pop-ups than ever!

Check out that precipitous decline in BABIP. It makes total sense too as grounders go for hits more frequently than fly balls, so all those extra flies, and especially those pop-ups, are really limiting hits on balls in play. I also wonder about shifting this year, as we have already seen some craziness when Joey Gallo was at the plate. Has fielding knowledge taken another sudden leap forward?

Let’s finish with perhaps the most surprising and oddest table:

First, this whole fly ball revolution makes me think batters are also pulling more of their fly balls. Pulled flies go for homers far more frequently than balls hit up the middle or to the opposite field, so if batters are trying to hit more fly balls to up their power game, it would follow that they’d want to pull those flies as well. So far, that hasn’t happened, after a spike last year.

Batters have held their Hard% gains this season, but oddly that hasn’t translated into homers on fly balls. Who would have guessed that HR/FB rate is actually below both 2016 and 2017 levels? From all the previous tables, I would have guessed the rate was up again. My wild guess is simply weather related in that these are the coldest days of the season and previous seasons include all April games, likely with some warmer (or less cold) weather.

It will be fun to follow these leaguewide trends as the season continues to unfold. Perhaps when every hitter becomes Ryan Schimpf, Schimpf himself will make a triumphant return, win a starting job, and five true outcome it like no one else (walk, strikeout, fly ball, pop-up, homer).