Tanner Roark Did It — Can He Do It Again?
We’ve already spent some time with Tanner Roark’s breakout season and it’s mostly about that two-seamer and getting strike one if you ask him. Let’s focus on those things first.
The bad news first. First strike rate isn’t super sticky year-to-year. The correlation is .479 year-to-year, meaning that this year’s first strike rate describes 23% of the variance in next year’s first strike rate. That’s as weak as the year-to-year relationship of home runs per nine innings, or a little bit less than half as strongly correlated as strikeout rate.
Roark may have been above-average in that regard for two years, but that doesn’t mean he’s necessarily going to manage the feat again next year. If you throw 70% strikes on the first pitch, maybe batters start swinging more at the first pitch and then maybe you start throwing fewer first pitch strikes. However it works, this isn’t a skill we can bank on in a 200-inning sample.