FORT MYERS, Fla. -- After posting a 3.10 ERA and strong peripheral stats in 10 starts as a rookie in 2015, the Twins had high hopes for right-hander Tyler Duffey last year.
But Duffey struggled in spring with a 7.30 ERA, and ultimately opened the year at Triple-A Rochester. It was a sign of what was to come from Duffey, who went through a rough sophomore season with the Twins, posting a 6.43 ERA in 26 starts.
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Duffey, who relies heavily on his two-seam fastball and curveball, said he believes a lack of command was an issue as well as falling into predictable patterns with his pitches.
"I think I missed some [location] and overused some things," Duffey said. "I really relied on my sinker down and in. Away to lefties, in to righties. But hitters figure out what you're doing. Toward the end of the year, I started mixing the fastball glove-side and throwing my fastball up in the zone. So the pitches were fine, it was just the timing and location."

As a result, Duffey focused more on fastball command during his bullpen sessions this offseason, which fits right into what pitching coach Neil Allen is doing this spring -- making his pitchers throw at least three out of five fastballs for strikes to both sides of the plate before moving on to their offspeed pitches.
"Last year, my fastball command wasn't good when I got here and it got me behind," Duffey said. "It's a big goal of everybody's this spring. Neil has really been pushing that to work on location."
Duffey has a believer in manager Paul Molitor, who thinks he has the stuff to be an effective starter. Molitor also pointed to the visible frustration Duffey shows on the mound as something he can improve on.
"We talked a lot about his ability to try to maintain his poise," Molitor said. "I think he's just trying to find that balance of how to use his personality in his favor more consistently. But his stuff has not backed up from where it was when he pitched a lot of big games for us in 2015. He has a component of how he's using it and throwing it where he wants to, and then the mental side."
Duffey, though, will have his work cut out for him this spring, as he's one of several candidates competing for a spot in the back end of the bullpen, along with Jose Berrios, Trevor May, Ryan Vogelsong, Justin Haley, Adalberto Mejia and Stephen Gonsalves.
It could mean Duffey starts the year as a reliever or could be optioned to Triple-A Rochester as a starter to give the Twins depth and allow him to work on his changeup. But Duffey, who was a reliever during his time at Rice University before being drafted by the Twins in 2012, said he's open to moving to the bullpen if it means it helps the team and he gets to remain in the Majors.
"I've done it before, so even when I'm starting, I still feel that closer in me from college," Duffey said. "Whatever they want me to do, I'm going to do. I'm very open to both."