Using Whiff Rate To Find Bounce-Back (And Breakout) Fantasy SP Candidates

Generally speaking, more swings and misses is good. But when those swings & misses aren't leading to a lot of strikeouts, it represents an opportunity to find potentially undervalued fantasy starters.

Let’s get this out of the way first.

If last year is anything to go on, if a pitcher has a high whiff rate, when all is said and done for the season, their respective strikeout rate should be fairly high (also good) as well.

Ok, so not every single pitcher with a high whiff rate is going to have a high strikeout rate when all is said and done.

Take Grant Holmes, for example. He finished in the 92^nd percentile in whiff rate last year (32.4%), but his strikeout rate (24.8%) finished in the 65^th percentile.

Similar statistical pairings were true for Daniel Hudson (91^st percentile in whiff rate, 66^th percentile in strikeout rate), Austin Voth (89th percentile in whiff rate, 63rd percentile in strikeout rate), Ryan Fernandez (88^th percentile in whiff rate, 66^th percentile in strikeout rate), and Alex Faedo (87^th percentile in whiff rate, 45^th percentile in strikeout rate).

But most of those pitchers spent the entirety of 2024 as full-time relievers – Holmes was the lone exception, though he made just seven starts in 26 appearances, thus giving them a smaller sample size for things to even out over the course of the season.

With starters, it was a different story last season.

(And it is worth mentioning, as an aside, that it’s possible that sequencing can sometimes play a factor here, particularly with starters and missing bats when looking at whiff rates compared to strikeout rates. That, and specific pitch arsenals and plans of attack for different hitters, are worth keeping in mind here.)

Last season, among full-time starters who made at least 15 starts, 24 finished with a whiff rate that ranked in the 75^th percentile or better. Reese Olson of the 24 pitchers to qualify statistically with a whiff rate in the 75^th percentile, finished with a 28.7% whiff rate. Hang on to that bit of info for later.

• Garrett Crochet: 93^rd percentile whiff%, 98^th percentile K%

• Dylan Cease: 92^nd percentile whiff%, 89^th percentile K%

• Jack Flaherty: 91^st percentile whiff%, 90^th percentile K%

• Cole Ragans: 90^th percentile whiff%, 88^th percentile K%

• Tarik Skubal: 90^th percentile whiff%, 91^st percentile K%

• Logan Gilbert: 89^th percentile whiff%, 80^th percentile K%

• Freddy Peralta: 87^th percentile whiff%, 81^st percentile K%

• Chris Sale: 86^th percentile whiff%, 94^th percentile K%

• Tyler Glasnow: 85^th percentile whiff%, 95^th percentile K%

• Carlos Rodon: 84^th percentile whiff%, 75^th percentile K%

• Jared Jones: 84^th percentile whiff%, 73^rd percentile K%

• Grayson Rodriguez: 82^nd percentile whiff%, 75^th percentile K%

• Sonny Gray: 82^nd percentile whiff%, 91^st percentile K%

• Ryan Pepiot: 82^nd percentile whiff%, 74^th percentile K%

• Hunter Greene: 81^st percentile whiff%, 81^st percentile K%

• Clarke Schmidt: 79^th percentile whiff%, 74^th percentile K%

• Michael King: 78^th percentile whiff%, 81^st percentile K%

• DJ Herz: 78^th percentile whiff%, 81^st percentile K%

• Reid Detmers: 77^th percentile whiff%, 83^rd percentile K%

• Ronel Blanco: 76^th percentile whiff%, 63^rd percentile K%

• Luis Gil: 76^th percentile whiff%, 77^th percentile K%

• Yusei Kikuchi: 76^th percentile whiff%, 84^th percentile K%

• Bailay Ober: 76^th percentile whiff%, 78^th percentile K%

• Reese Olson: 75^th percentile whiff%, 39^th percentile K%

So, generally speaking, if you log a high whiff rate, a high strikeout rate will probably follow. There are some obvious exceptions there, which is to be expected with such a large number of starters. But generally speaking, if the whiff rate is very good and is significantly ahead of the strikeout rate, similarly, very good fantasy production should follow with increased strikeouts.

(Also, one more aside, you can’t always draw a straight line from a higher number of swings and misses and strikeouts to overall success and effectiveness, but it certainly helps when there are more strike outs than grounders, line drives or fly balls).

And while it’s not a total guarantee that every single pitcher with a high whiff rate and a lower (comparatively) strikeout rate will see a spike in strikeouts moving forward, it is a potentially useful way to find bounce-back (and breakout) candidates when sifting through fantasy rosters trying to identify undervalued potential impact trade targets.

These are four of those potential impact trade targets.