Yesterday, Nathan Karns made his Rays debut, and he was very good. He gave up just two hits and two walks in seven innings while striking out eight Blue Jays. Now of course, major league hitters haven't had a chance to study and adjust to Karns. They will, because major league hitters are very good at hitting. Karns won't always pitch like this. He's not the second coming of Matt Moore (we're still hoping that Matt Moore can be the second coming of Matt Moore) -- if he were, he would have better minor league numbers and he'd have been called up months ago.
Now that we've gotten that out of the way, let's talk about the good stuff. Nathan Karns's curve ball is a truly amazing pitch. I won't speak for the entire league, but Karns's curve has a strong case for being the best pitch in the Rays organization. It's that good.
I knew what to expect, because I scouted him -- based on a very limited number of innings in front of major league PITCHf/x cameras -- last offseason. Karns has a plus fastball with mid-90s velocity and decent movement. His calling card, though, is a power curve, that, with mid-80s velocity, is among the hardest thrown curves in baseball. Take a look at the second pitch in this video, a strikeout of Kevin Pillar.
Yes, friends, that's an 87 mph curve ball. Pillar's mind is blown, and so is mine.
Of course, throwing the curve this hard comes at the cost of movement. This is the graph I made last offseason. You can see that Karns's curve has less vertical drop than that of any other Rays curves. If it averaged 74 mph, it would be a bad pitch, but at 84 mph it does nicely.
That's all data from last year, though. What was Karns's movement like last night? Using the PITCHf/x numbers from Brooks Baseball, I placed last night's average curve (same velocity) on the old graph, and marked the new one with an awesome red lightning bolt.
Maybe it's just one game and the cameras are off. Maybe he was tired last year and his arm was dead. Both of our sample sizes are very small here, so there could be any number of things going on, but it sure looks like Karns's curve has improved. It showed the same vertical break that Matt Moore and David Price get, but with a bit more horizontal break and higher velocity.
I'm not a scout -- I'm just a guy who looks at PITCHf/x for a hobby -- so take this for what it's worth, but I'd be tempted to give the pitch an 80 grade. There is literally no pitch in the majors quite like it. If Karns can throw his plus-plus curve and his plus fastball for strikes, then his floor is Dellin Betances, the young shut-down reliever for the New York Yankees. If he can do anything else (and yes, he does know how to throw a chagneup, even if he only threw it once last night), then he's a starting pitcher with a bright future.