Kansas City Royals pitcher Danny Duffy has one of the more interesting names and stories in all of baseball. He’s a left handed pitcher of relatively slight build, who happens to throw the ball almost 100 mph. He’s bounced around roles in Kansas City; he’s pitched in the pen and in the rotation.
In 2012, he saw his velocity tick up in spring training. A full-time starter then, his fastball averaged 95.5 mph and touched 99.5. The generous among us might round that up to 100; I didn’t. Then, he tore his UCL and missed a crucial year of development while rehabbing his gifted left elbow and that derailed things for a time.
See, Duffy has always had the talent. His minor league numbers indicate that his development was relatively painless. He’s thrown 433 innings in the minors since he was drafted in the third round out of high school. He’s got a 2.87 career ERA and has struck out well more than a batter per inning. At the major league level, things haven’t been as smooth. His rookie year resulted in a 5.64 ERA. Things looked a bit better in his sophomore campaign, though he was walking far too many people, and then the UCL snapped.
Duffy has spent most of the last three years working his way back into proper form. The Royals did him no favors by bouncing him between the minor league rotation, major league rotation, and bullpen. But he’s still just 27 and appears to be taking another huge step forward. It’s evident not just in his stuff, but more importantly in his walk rate.
Walk rates aren’t the most sexy thing, but with Duffy and his gifted arm, it’s where the struggle has always been. We’ll get to the raw stuff here in a second, but first:
Duffy has worked his walk rate way below average this year for the first time in his career. In this stat, that’s a great thing. He’s currently sporting a 1.5 BB/9, which would slot him into Zack Greinke territory if he had enough innings to qualify. That likely won’t last, but….
Duffy’s walks are finally under control and his stuff is finally back.
Duffy spent some time in the bullpen this year, where fastballs and offspeed stuff generally gain an extra tick of velocityas they’re thrown with more effort, but this is still a promising trend.
Duffy is finally back to his pre-TJ fastball velocity, and he appears to have that same rising life, but with the little added sideways movement that seems to come with age.
I watched Duffy’s start last night as I was researching this post. Duffy impressed. He shut out the Orioles through 6 innings and struck out 8 against no walks. He appeared to tire as he pitched into the 7th for the first time all year and he gave up two solo homers to Adam Jones and Matt Wieters before exiting. Still, on 80 pitches his final line on the night was 6.1 IP, 9 K’s, 0 BB, 5 hits, 2 earned. He continued his new found trend of being really good.
But what struck me and my decidedly amateur scouting abilities as most notable concerned Duffy’s changeup usage. He threw the change a full 25% of the time last night, and has thrown it about 15% of the time on the year. This is up from about 9% a year ago. Why the change in change usage? Seems pretty simple to me. He’s allowed just a .194 OPS against the change, which is by far his best against any pitch.
A year ago, Duffy’s primary secondary offering was his curveball. He threw it about 23% of the time. This year, that’s been passed by his changeup and he’s throwing the curve just 12%. This is probably easier in a chart.
It’s not that his changeup is drastically different. It still has the same basic characteristics, with maybe a bit more horizontal movement these days. He’s just using it more, which is making life more difficult for hitters. When you’re a left hander that throws 95, doesn’t walk anyone, and can confidently throw two offspeed pitches for strikes, life is good.
Duffy likely won’t keep up that insane .194 OPS figure against his changeup. He probably will walk more people than he has to this point, and he probably will lose a tick off his fastball as the uptick from bullpen innings is drowned by starting through the summer. But all that is OK. He’d still have his three pitches, and a 95.0 mph fastball is still excellent. It appears like he’s finally cashing in on all that talent.