Reviewing The 2017 Starting Pitcher Strikeout Rate Downsiders

Yesterday, I reviewed my 2017 starting pitcher strikeout rate upsider list, which produced embarrassing results. Let’s hope the downsider results look much improved. Once again, this list was compiled by using my pitcher xK% equation to identify starters whose 2016 xK% marks were significantly above their actual K% marks.

This was a slightly better showing, but still disappointing. It was a mixed bag with two of the five pitchers losing points on their strikeout rates, two raising their rates, one of them significantly, and the fifth essentially flat versus 2016.

Ivan Nova may have been one of the more valuable names on this list. He enjoyed a strikeout rate rebound in 2016 and was going to get a full season in as a National League starter. So it would have been easy to be convinced another strikeout rate surge was coming. But xK% begged to differ, as he’d have to improve his underlying skills, to go along with the NL strikeout boost, just to stay on par with his 2016 strikeout rate. What’s interesting is that both his curve and changeup were excellent swing and miss pitches, but he throws his weak fastball too often. At least the sinker gets grounders, but the four-seamer doesn’t get those or whiffs. I’m not sure why he continues to throw the pitch.

Jameson Taillon’s minor league record suggested strikeout rate upside, which is why you can’t just look at a rookie’s debut MLB xK% mark and stop there. However, for a pitcher with a mid-90s fastball, we expect more on the strikeout front. The problem is his pitches just don’t induce whiffs. His curve only generated a SwStk% of 11.9%, after a 10.4% showing in 2016, and his changeup was in the high single digits. The grounders are nice, but the results of his repertoire so far don’t give much reason for excitement.

Pretty amazing that Jaime Garcia battled not only a move to the AL, but also a decline in his underlying strikeout rate skills, and yet still managed to post a strikeout rate right in line with his career average. With his ground ball rate still intact, I might still be interested depending on where he ends up.

Woah, didn’t see that strikeout rate surge from Jose Quintana coming! It was mostly due to a spike in called strike rate and good old fashioned lady luck. Want to understand how fortunate he was? He led all of baseball’s starting pitchers in K%-xK% discrepancy. That said, a full season in the National League should offset some of that expected regression.

Jerad Eickhoff was a popular sleeper heading into the season, though his underlying skills didn’t justify a 20% and change strikeout rate. This year, he only marginally improved those underlying skills, and his strikeout rate remain almost unchanged. He scrapped his changeup and threw his curve ball more frequently, which was a reasonable switch given the latter’s superior SwStk% generated. The problem was he forgot how to throw strikes, which boosted his walk rate and made it easy for batters to lay off his slider (big decline in O-Swing%). I’ll speculate in NL-Only, but that’s all.