SURPRISE, Ariz. -- The origin of Royals left-hander Danny Duffy's breakthrough season in 2016 can be traced to 2014.
That's when the Royals experimented with Duffy in the bullpen and he posted a 2.16 ERA in six appearances before returning to the rotation.
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The next season, Duffy was back in the rotation and stayed there until struggling in late August and September. He finished that season in the bullpen, posting a 0.00 ERA in six appearances.
Hmmm. The Royals have converted many starters (Wade Davis, Luke Hochevar, et al) into shutdown relievers in recent years, but the decision to attempt the same with Duffy was debated. The Royals liked Duffy's success out of the bullpen so much that he started last season in that role. He didn't disappoint, posting a 3.00 ERA in 16 games.

But as fate would have it, injuries to the rotation forced the Royals to make Duffy a starter again. And this time, he looked like a different starter. Duffy posted a 3.51 ERA and a 12-3 record in 26 starts last year, attacking each batter as if he were still a short-inning reliever.
Don't pace yourself. Attack.
The new approach worked, just like it had years ago with former Royals ace Zack Greinke, who used a bullpen role to eventually become more aggressive as a starter en route to winning an American League Cy Young Award.

"Being in the bullpen was really beneficial," Duffy said. "I had mostly really short stints in the bullpen, and having some success there really helped my confidence.
"And I took that approach, of just attacking, back to when I started again. It changed everything."
Duffy's turnaround as a starter in 2016 inspired manager Ned Yost to call the 28-year-old one of the elite left-handers in the Majors. And for Yost, it was an easy call to make Duffy the Royals' Opening Day starter on Monday in Minnesota.
"He earned it," Yost said. "He has emerged as an ace."

Duffy, who will be making his first career Opening Day start, said he was deeply moved when he got the news.
"It's such an honor," Duffy said. "I've been in 10 camps now and put in a lot of hard work to get to this point. So, yes, it was an honor. It was rewarding."
Duffy said he has no intention of changing his new, aggressive approach, even at the suggestion that it might be impossible to go all out with every hitter as a starter.

"I kind of disagree," Duffy said. "I understand about the whole fatigue factor. But even when I had just 70 percent left in the tank last year, I would still go 100 percent, all out, with that 70 percent.
"Obviously, your velocity will drop after a while, but that's what I do. It brought me success. I just try to condition myself to keep up my velocity, even in the seventh and eighth."
Duffy doesn't worry if other starters still have success with an old-school approach that favors pacing.
"Hey, there's no wrong way to eat a Reese's," Duffy said. "Everyone gets things done in different ways."