When Zach Britton Was Hittable

It's certainly not an uncommon path for a middling or failed starting pitcher to convert to a reliever and find success. Many of them, though, don't find nearly the level of success that Zach Britton has discovered after moving to the bullpen in 2014.

Britton has been tremendous since becoming a full-time reliever, seemingly improving in some meaningful way each season while never posting an ERA above 1.92 and improving his fielding independent pitching results in three straight seasons.

As you'd expect, Britton had a much different pitch repertoire as a starter. He mixed in four pitches (scrapping the slider after 2012), including a four-seam fastball nearly 30% of the time.

Data via Brooks Baseball

Britton has refined his sinker, as he throws the bowling ball style pitch nearly 90% of the time out of the bullpen. But while his overall mix of pitches wasn't generating enough swings and misses, his sinker was still inducing an impressive number of grounders.

Data via Brooks Baseball

Britton is currently posting groundball percentages of 80%, which is ridiculous, but his sinker results while in the rotation were promising. However, he wasn't able to blow the sinker past nearly as many hitters, something that he's improved on each season as a reliever.

Data via Brooks Baseball

That's what can happen when you go from throwing a pitch in the 92-93 mph range to 96-97 mph. Still, when Britton is seeking a strikeout, his curveball is the superior pitch. But when you throw a pitch nine out of 10 times, it's almost always your go-to offering.

Maybe the biggest problem for Britton as a starter was that his four-seam fastball was not an effective pitch. He threw the pitch the second-most often, and it was easily the pitch that opposing batters hammered the most.

Data via Brooks Baseball

It can be fun to play the what-if game: what if Britton could convert back to a starter now? Could he have found more success if he simply threw even more sinkers as a starter? What could have happened if Britton, Brian Matusz, and Jake Arrieta et al. were handled differently during their development? We don't know the answers to those questions, but we do know that the current version of Britton is one of the very best and most dominant relief weapons in the majors. That's remarkable and something to treasure.

Photo via Keith Allison