Joe Musgrove’s Weird One-Seam Sinker

We first encountered Joe Musgrove‘s one-seam sinker around the All-Star break, when he was kind enough to show us the grip before his appearance in the Futures Game. I’d never seen a one-seam grip before, unless you count the one Zach Britton showed us. While we could spot glimpses of the sinker in the Futures Game and in his minor-league games, it wasn’t until Musgrove came up and started pitching in the big leagues that we could truly put his pitch in the context of other big-league sinkers. It’s weird. Here’s that grip, again. It’s notable for a few reasons. It’s not a four-seam grip because he’s not pulling down on a seam to create the down-up spin that gives four-seam fastballs their trademark upwards “ride.” And it’s not a two-seam grip because he’s not pulling down on a seam with his middle finger, which traditionally creates the sideways spin that gives two-seam fastballs their sideways “fade.” That one-seam sinker grip. If you take away both of those movements, what are you left with? Downward movem