For the second straight season, we witnessed the highest strikeout totals in MLB history. There was an average of 8.25 strikeouts per MLB game in 2017, up from 8.03 strikeouts per game in 2016. Strikeouts have increased in baseball every year since 2005, and there is no indication that this trend will reverse any time soon.

Among qualified starters, Boston's Chris Sale led the pack with an astonishing 36.2% strikeout rate in 2017, making him one of four players to have a strikeout rate over 30%, along with Max Scherzer, Corey Kluber, and Robbie Ray. To put that number in context, only two players had a strikeout rate over 30% in 2016; five seasons prior to that, in 2012, no qualified pitcher had a strikeout rate greater than 30%.

As strikeouts increase across the league we can expect several pitchers to benefit from this change. Let's look at three beneficiaries of the strikeout spike, and three pitchers that were not so lucky.

Strikeout Risers

Jose Quintana, CHC - 26.2% K rate in 2017 (20.9% career rate)

Between 2013-2016 Jose Quintana was among the most consistent pitchers in baseball. His ERA stayed between 3.20 and 3.51, his strikeout rate stayed between 19.7% and 21.6%, and his K-BB was between 13% and 15.6%. His unwavering reliability has always made Quintana an appealing fantasy option, which is why his spike in strikeout rate last season was so surprising. After never having a K/9 above 8.00, Quintana finished with a 9.87 K/9, and he also finished with an ERA above four for the first time in his career. Quintana’s disparate 2017 season begs the question, was this an outlier or did the soon to be 29-year-old change his pitching style?

Most of Quintana’s 2017 numbers suggest that his uptick in strikeouts was a fluke. His swinging strike percentage was a pedestrian 8.4%, aligning almost perfectly with his career swinging strike rate of 8.5%. The most drastic change that Quintana has implemented throughout his career was an increase in sinker usage. After throwing the pitch less than 10% of the time prior to 2015, his usage has increased over the last three seasons, up to 27.3% in 2017. Normally a drastic increase in pitch usage would be the obvious reason for the strikeout rate spike, but the sinker is hardly a swing-and-miss pitch for Quintana, netting just a 5.54% swinging strike rate in 2017. Quintana did see an increase in his changeup swinging strike rate from 7.67% prior to 2017 to 12.23% last season. The increase in changeup effectiveness may allow Quintana to maintain his strikeout rate increase. He should be drafted with the expectation that he’ll put up numbers similar to his White Sox days, but K/9 over nine is certainly within reason.

Trevor Bauer, CLE - 26.2% K rate in 2017 (22.6% career rate)

In 2017 Trevor Bauer’s strikeout rate rose from a career average of 22.6% to 26.2%, good for a 10.00 K/9, 13^th best among qualified starters. Even with this increase in strikeouts Bauer’s 2017 4.19 ERA is only a slight improvement over his career 4.36 ERA. Despite the lack of improvement in run prevention Bauer’s rise in strikeouts appears to be legitimate. His career low 3.60 xFIP and 3.80 SIERA coupled with a career high .337 BABIP against and 16. 1% HR/FB rate suggest that Bauer’s ERA was inflated by misfortune. The biggest change that Bauer made was an increase in curveball usage, up to nearly 30% after using it about 15% of the time prior to 2017. The curve has always been Bauer’s go-to pitch when ahead in the count, and his most effective pitch, with a .160 BAA and .085 ISO against for his career, and if he continues to use it 30% of the time he should be able to maintain an above league average strikeout rate and his ERA should better align with ERA-predictor metrics.  If Bauer’s BABIP against and HR/FB rate regress to his career averages he should be looking at his first big league season with an ERA under four to go along with his increased strikeout rate. Everything is pointing to Bauer progressing from beyond a mixed leaguer streamer to a dependable starter.

James Paxton, SEA - 28.3% K rate in 2017 (23.3% career rate)

Going into 2017, James Paxton was one of the hottest breakout candidates in fantasy baseball. When healthy, he delivered consistently with a 2.98 ERA and 10.32 K/9 in 136 innings. For his career, Paxton has a 23.3% strikeout rate, but in 2017 it went up to an elite 28.3%. Like Trevor Bauer, Paxton’s success coincided with an increase in curveball usage. After suffering a myriad of injuries between 2013-2016, Paxton was forced to throw the pitch less, using it just 13.7% of the time in 2016, but in 2017 he threw it 21.3% of the time. Paxton’s curve gave batters fits last season, with a 17.82% swinging strike percentage and .155 BAA. As long as he continues to use his curveball heavily, there is no reason to believe his strikeout numbers and overall performance is a fluke. Due to his injury history, he should be treated similarly to Rich Hill or Lance McCullers in drafts. 30 starts cannot be expected, but elite production is possible when the player is healthy.

Strikeout Fallers

Cole Hamels, TEX - 17.1% K rate in 2017 (23.0% career rate)

2017 was a disastrous year for Cole Hamels. He finished with an ERA above four for the first time since 2009, he had a career-high 36% hard contact rate allowed, and his strikeout rate was a measly 17.1%, about six percent lower than his career average. What’s most surprising is that Hamels managed to put up these numbers with an extremely fortunate .251 BABIP, which contributed to his unsightly 4.90 SIERA. At 34 years of age and over 2,300 MLB innings on his left arm, is there any hope for a Cole Hamels bounce back?

His biggest issue, one that began in 2016, was the deterioration of his signature changeup. Once considered among the best changeups in baseball, Hamels has not been able to rely on his put-away pitch over the last two seasons. Whiffs on his changeup are down four percent over the last two seasons compared to the first ten of his career. When batters have connected with the changeup they’ve hit it hard, with a .181 ISO against compared to his career .109 ISO against prior to 2016. Over the last two seasons, Hamels has actually surrendered more home runs with his changeup (14) than his fastball (nine) despite throwing the pitch 318 fewer times over that span. The only argument that could be entertained for a Hamels turnaround is health. He missed two months in 2017 with an oblique injury, and the injury may have lingered and affected his season-long performance. He suffered an oblique injury Since his decline began in 2016 it seems unlikely that he will ever return to being a top-30 starting pitcher.

Michael Fulmer, DET - 16.9% K rate in 2017 (20.4% in 2016, his only other season)

The 2016 AL Rookie of the Year had his share of struggles in 2017. Despite maintaining a solid 3.83 ERA, his 4.48 SIERA and 3.5% drop in strikeout rate down to a mediocre 16.9% suggest that Fulmer took a bigger step back than his surface statistics indicate. Fulmer’s biggest issue last season was the lack of effectiveness with his secondary pitches. Fulmer allowed a .232 BAA against and .167 ISO against with his changeup in 2017, where in 2016 he allowed a .167 BAA and .031 ISO against, and his slider had similar regression.

Since Fulmer has had only two seasons in the majors there is no established baseline for his secondary pitch performances or his strikeout rate, making it hard to tell which version is the real Michael Fulmer. Fulmer also underwent ulnar transposition surgery on his elbow in September, meaning that his decline in performance may have been injury related. He’s a talented pitcher and will be just 25 on opening day, so there is room for not only a bounce back but growth. Given the fact that he is recovering from elbow surgery, has only 323.2 major league innings under his belt, and was not a high strikeout pitcher in his breakout 2016 campaign with just a 20.4% strikeout rate, a bounce back should not necessarily be counted on. Fulmer could be a solid number three in 2018, but most likely won’t be a reliable strikeout source.

Julio Teheran, ATL - 18.6% K rate in 2017 (20.6% career rate)

After having a 22% strikeout rate in 2016 Julio Teheran’s strikeout rate dropped down to 18.6%, the lowest of his career. Teheran also had the worst season of his career, with a 4.49 ERA and 4.89 SIERA, both career highs. A lot of Teheran’s issues came from pitching in the brand-new SunTrust Park, where he had a 5.86 ERA and 17.5% strikeout rate versus a 3.14 ERA and 19.8% strikeout rate on the road. He also went to his slider less in 2017, using it only 19.4% of the time, the lowest slider usage of his career. Instead he relied more on a mixture of his four-seam fastball and sinker, which likely contributed to his struggles since Teheran’s slider has always been his most effective pitch. The good news is there appears to have been no skill deterioration for the 26 year old, and if he regains the ability to command his slider effectively Teheran should be able to bring his strikeout rate back over 20% again. Hopefully a second year at SunTrust will allow him to adjust to the park and pitch better at home. Teheran could certainly bounce back in 2018 and is worth taking a risk on as a number three with number two upside in drafts.

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