The Roar
The Roar


Sabermetrics: Understanding the rise of pitchers

Roar Rookie
12th May, 2013

I pose this question to you. Can sabermetrics explain the growing trend towards pitching dominated baseball? The answer: Yes it can!

Being a die-hard baseball fan, along with being a part time nerd, my fantasy baseball team is set on these figures (however bad my team is).

One spot that stumps the team is the pitching slot. On any given night, anyone can pitch a perfect game (if Phil Humber can do it, who says Jeremy Gutherie can’t?).

This is due to the increased knowledge of stats, with the combination of smarter pitchers, receding hitters and platoon-focused managers.

So why is pitching so important? Let’s look at the basic stats between 1990 and 2013:

Pitcher/batter related statistics
A crucial stat for any pitcher is the rate at which they walk hitters. Generally, the higher walk (BB) percentage, the more runs scored.

Looking at raw statistics alone, walk percentages are down, which means more chance for a strikeout, right?


I lied. Of course they’re up. 2012 saw strikeout levels sit at 19.8 percent, the highest level recorded ever.


2013 looks the same, with over 20 percent of at bats (ABs) ending up in a punchout. Lastly sits the strikeout-to-walk (K/BB) ratio.

What does that show? Pitchers throw better, have better control, and can punch out more guys than ever before.

Pitcher related statistics
While earned run average (ERA), ground ball (GB) percentage and fly ball (FB) percentage are simple to understand, at times they are difficult to correlate to the real skill of a pitcher.

A system that tries to fix this is SIERA (Skill Interactive ERA), which puts more emphasis on strikeout pitchers (generate weaker and less contact) and taking into account the GB/FB ratio.

Essentially, it shows the effectiveness of a pitcher through all his statistics (so a general round-up).

Since 2002 (thank you excel for wasting my time in trying to format you), less fastballs are being thrown, and with that comes the increase in off-speed pitches.

This new age pitching keeps batters off balance, which would lead to the higher strikeout (K) percentage shown.

Oh, and did I mention that they throw harder too now?


Since 2004, fastball velocity has risen from 90 mph to 91.2 mph. Not a big difference, but enough to make the batter swing a little later.

But, I’m sure you’re all screaming that the faster a ball travels, the less break is imposed on it. After all, that’s physics at work.

But while all balls fall towards the ground, this is using a hypothetical pitch with no spin. Since fastballs (usually) have backspin rotated on the balls, it causes it to go upwards, at least hypothetically, while curveballs rotate down.

Put simply, without rummaging through the data too much, fastballs have more break on them, which is why batters are missing high this year (that will be explained in the next article). Curveballs are developing more break as well.

This shows pitcher strength and continuality while being able to be more aggressive towards hitters.

Sabermetrics really is a beautiful thing to look it, especially when analysing who is the best pitcher in the majors (*cough* Clay Bucchlolz *cough*).

Pitchers have really gained traction over the years, and pitching duels are now a lot more common, as managers and players become more aware of pitch counts (something I didn’t even mention), hitting tendencies and the like.

Next week, more sabermetrics (woo). But this time, it’s analysing hitters, and why they are more crummy now than they were in the past. But until then, go Red Sox.