Potential Starting Pitcher Walk Rate Regressers

Yesterday, I used my xBB% equation to identify starting pitchers whose actual walk rates were most above their expected marks. This group should be expected to enjoy a decline in their walk rates moving forward. Today I check in on the guys who may be due for regression. This is your list of fantasy relevant starting pitchers whose xBB% marks are most above their actual walk rates.

Drew Smyly was a popular sleeper as he returned to the Tigers rotation this year, but he’s only received two starts all season so far. He’s shown excellent skills, but doesn’t throw a high enough rate of strikes to maintain a walk rate around 7%. His F-Strike% is also at a scary low 51.7%. Given a likely innings limit and some regression in his strikeout rate, he could become a sell high candidate soon.

Marco Estrada’s strike percentage is currently at a four-year low, while he’s lost the ability to throw first pitch strikes. Yet, his walk rate stands at a career best mark. Hmmmm. Estrada has displayed extremely consistent skills over the year and I’ve been a fan, but his control is something to monitor.

Zack Greinke is actually throwing the highest rate of strikes in his career since his 2004 debut. And even with just solid, yet unspectacular, strike rates, he’s managed to always maintain strong control numbers. He looks to be one of many examples of the shortfalls of the xBB% equation. He seems out of place on this list.

C.J. Wilson has never displayed good control, but this year he’s throwing the lowest rate of strikes in his career. It hasn’t affected his walk rate yet, but that’s perhaps because he’s also striking out batters at the highest rate of his starting career. Given that all those strikeouts are primarily driven by a ridiculously inflated looking strike rate, I’d expect that mark to decline and the balls to begin leading to walks.

Chris Sale’s percentage of strikes is at its lowest since his 2010 debut. And sure enough, he’s also currently on the DL with an elbow injury. That seems like the likely explanation for the worsened control, but given his delivery, you have to wonder if the injury is more serious than we’re hearing.

Tim Lincecum is showing by far the best walk rate of his career, but xBB% isn’t buying the improved control. His strike percentage is barely above his career average and his career walk rate sits at 9.1%. His rate of swinging strikes is also down significantly, offset somewhat by a career best looking strike rate. Normally, I would advise buying low on a pitcher with a 3.15 SIERA and 5.96 ERA, but Lincecum scares me. I think his peripherals are due for a dive and that SIERA is going to jump. He’s still suffered from some terrible fortune of course given that insane .395 BABIP and 25% HR/FB rate, but if he rebounds to a 4.00 ERA or so, that’s really not worth much in a shallow mixed league.

Although Hiroki Kuroda’s strike percentage hasn’t declined in a straight line, the trend is clearly in that direction. His fastball velocity is down a bit, he’s generating fewer swinging strikes and he’s allowing the highest fly ball rate of his career. He had been defying the effects of aging given his amazing consistency, but at age 39, the end of him being a strong and undervalued fantasy asset may be coming to an end.