Inside Baseball: Felix and The Verducci Effect

Sunday’s column was a further look at the Mariners’ signing of Felix Hernandez for five years. Which led one reader to bring up the interesting specter of the Verducci Effect.

The Verducci Effect is named for Sports Illustrated writer Tom Verducci. He identified the fact that young pitchers who have an increase of 30 innings or more over the previous season tend to underperform or get injured the following year.

Here’s an article from that identified seven pitchers who were susceptible to the Verducci Effect heading into 2009: Jon Lester, Cole Hamels, Chad Billingsley, John Danks, Mike Pelfrey, Tim Lincecum, and Jair Jurrjens.

Lincecum, obviously, suffered no ill effects; Lester was probably better than the previous year, although his ERA rose slightly; and Jurrjens was outstanding. But Hamels saw his ERA rise by 1.23 while the batting average against him went up 46 points, Billingsley’s ERA went up nearly a run, and Danks’ rose by 0.45. And Pelfrey couldn’t get anybody out.

What does this have to do with Felix? Well, he’s a candidate for the Verducci Effect this coming year. After seasons of 191, 190 and 201 innings, Hernandez threw 238 last year.

As Verducci wrote in 2008: “It’s like training for a marathon. You need to build stamina incrementally. The unofficial industry standard is that no young pitcher should throw more than 30 more innings than he did the previous season. It’s a general rule of thumb, and one I’ve been tracking for about a decade. When teams violate the incremental safeguard, it’s amazing how often they pay for it.”

I’m not saying that’s going to happen to the Mariners. But it is one more reason to give pause before being all giddy about signing a pitcher to a five-year deal.

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