Tyler Duffy

With the Vikings season over, NCAA football done, and no pro football until tomorrow, I thought I'd talk baseball again. Specifically, Twins pitching.

Tyler Duffy threw 58 innings for the Twins last season in 10 starts. His final ERA was 3.10.

You can see why the Twins  and Twins' fans are high on him.

So why am I writing this blog? Well, as long as you ask, there appears to be one glaring potential problem with him. I'm not saying there IS a problem, but I see one developing in the not-too-distant future: Arm trouble.

Minors included, Duffy threw a total of 196 innings last year, so he obviously has what it takes to throw in the majors.The problem is pitch selection based on his capabilities. He has a fastball clocked in the low-nineties, and by major league standards that's a little less than you'd hope for. Because of that pitch he relies on his curve ball A LOT, probably too much. His ratio last year was 58 percent fastball, 40 percent curve, and only 2 percent change-up.

Only ONE regular starter in the majors last year threw over 30% curveballs and that was Jose Quintana of the White Sox and he was 30.9%. There's a few relief specialists who have a higher percentage but they don't throw anywhere near the number of pitches or innings as a major league starter.

There's a reason why starters don't throw curves that often. It causes arm problems and shortens or destroy careers. Bert Blyleven says that stat is nonsense, but if you look at Bert, he is the ONLY exception to that rule in all of major league history. He threw 278 innings for the Twins when he was only 20 years old. He threw the curve better and more often than perhaps anyone in baseball history as well. He pitched into his late 30's before experiencing ANY arm trouble. But there literally is no one else in the history of baseball like him.

Everyone else who threw curve balls that often didn't last long. Duffy's selection percentage is probably not sustainable unless he turns out to be another Bert. History is not on his side.