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Danny Duffy’s make or break 2019

The Royals’ often injured “ace” is, well, recovering from injury... again. Can the Royals count on him to front the starting rotation after a disappointing 2018?

St. Louis Cardinals v Kansas City Royals Photo by Ed Zurga/Getty Images

Danny Duffy, as we all know, has electric stuff. He can’t seem to stay healthy enough to be the front-line starter Kansas City needs, though, averaging 25 starts and just 153 IP per year since 2014. Because of this, the Royals have to wonder how much they can count on Duffy to front the rotation.

I know what you’re thinking—Danny Duffy has actually been a pretty good starter since 2014. You’re not wrong. If you throw out a dismal 2018, Duffy has actually been a very good—even excellent, at times—starting pitcher. He started 99 games (with another 28 as a reliever) for a total of 612 innings and a 3.47 ERA from 2014 through 2017. So what am I raving about, exactly?

Duffy had a disastrous 2018 season, which saw him pitch horribly and get hurt yet again. He had a 4.88 ERA and 1.4 WHIP, losing the control he’d managed to harness back in 2014. In general, not only did fans lose confidence in Duffy, he had the demeanor of someone who’d lost confidence in himself.

Don’t get me wrong. I love Duffy and his “bury me a Royal” mantra. But I’m also not particularly fond of his DUI that saw him passed out at a Burger King. Yet what I really don’t love are the repeated injuries and trips to the IL.

In 2012 he went on the 15-day IL in May, before being transferred to the 60-day in June for Tommy John surgery. In September 2013, after recovering from Tommy John surgery, he landed back on the IL with a different injury. In 2014 he had the rib injury that kept him from being deployed much in the postseason, after a great year as both a starter and reliever in the regular season. In 2015, he landed back on the 15-day before pitching a career high 179 ⅔ innings in 2016.

Things were looking up for Danny after that season, but 2017 saw a couple of stints on the IL, along with the fallout of the aforementioned BK incident, and his innings dipped back below 150. That being said, according to FIP, Duffy was better in 2017 than 2016.

Most recently, of course, was the not-so-great 2018, which saw another yet another trip to the IL and was his worst year since his 2011 rookie campaign.

What went wrong in 2018? An increased use of his four-seamer was an effective pitch for him (batting average against was 40 points better than in 2017), but his secondary pitches weren’t working as usual. As Duffy’s fastball use decreased in prior seasons, he had actually improved as a pitcher—with his FIP dropping from 4.43, to 3.83, to 3.46 from 2015 through 2017. He seemed to have lost some feel for his other pitches last year, which correlated to his different pitch mix.

Pitch mix 2014-2018

As he ramped up his four seam usage in 2018, his FIP rose to 4.70, which was nearly as bad as the 4.82 (a career-worst) he posted in 2011. His sinker and slider use took the biggest hits in favor of the heater in 2018. His sinker has never been great, or even good, but in 2018 batters hit .345 against the pitch. Ouch.

The biggest hits to Duffy’s arsenal though, came against his previously dominant change and what had been a very good slider. Batters only managed to hit .183 and .187 versus his change in 2016 and 2017, respectively. In 2018, that number rose to .248 for a 61 point swing. The slider jumped from .245 in 2017 all the way to .296 in 2018, another big swing of 54 points.

Batting average against pitches—2014-2018

Not only were batters managing base hits off the secondary pitches, they were hitting them hard—slugging .409 against the change (up from .327 in 2017) and .574 versus the slider—a huge increase from .320 in 2017.

Slugging against pitches—2014-2018

What’s baffling is his continued use of the sinker, which hitters do very well against, in place of what was once an excellent curve. 2014 was the last year he used the curve heavily, and he held hitters to a .133 average against the pitch. He brought it back in 2018, using it 9.52 percent of the time and holding batters to a .213 average against.

Of course, there were also rumblings that Duffy was tipping pitches. That may have been the issue with his secondary pitches, which in turn made him less confident in his stuff. At one point in 2018 Duffy was only pitching from the stretch, trying to ensure batters couldn’t tell what they were about to see. Bottom line—a lot of things seemed to unravel for Duffy in 2018, leaving him scrambling for answers.

As Duffy ramps up for 2019, he should place a strong focus not only on his mechanics (and potential pitch-tipping) but also on pitch mix, bringing the secondary pitches back into the fold more as he tries to mirror his 2016-2017 success.

I’d suggest a mix of 35 to 40 percent four seam; 25 percent slider; 20 to 25 percent change; and bring the curve back around at 10 to 15 percent. After three straight seasons of averages well above .300 against the sinker—it’s probably time to let it go. If he wants to throw one here and there (like he used the curve from 2015 through 2017), so be it. But it shouldn’t be used more than 3 to 5 percent of the time—more of an occasional surprise.

Okay, now that we’ve solved that, how about the durability issue? Frankly, if he can’t hold up for more than 140-ish innings, it might be time to deploy Duffy much like the Brewers use Josh Hader. Plug him in for anywhere from 1 to 3 innings of dominant “stopper” relief. Not necessarily a closer, but just turn Duffy loose, allowing him to go 100 percent for shorter stints, but still in important, high leverage situations.

Duffy seemed to enjoy that mentality back in 2014, the no-holds-barred method of relief pitching—going all out, not having to pace himself for longer outings. The role seems to agree with him. As a reliever, he has a career 2.08 ERA and strikes out nearly 4 more batters per 9 innings than he does as a starter.

The mechanics and pitch mix are up to Danny and the pitching coach. We know he can put both together and be a very good starting pitcher. The question is: will his body allow it? That remains to be seen. If not, the Royals have a lot of young arms on the way. Maybe Duffy can slide into a new role to make way for the next generation in 2020 and 2021. It’s hard to know what we’ll get out of Duffy, really, but 2019 will go a long way to writing the rest of his story as a Royal.


Bob Ellis is a lifelong Royals fan. He has written in the past for Kings of Kauffman and Statliners. Follow him on Twitter @BobEllisKC