"Getting ready was the same as a start, but as far as attacking hitters, it was more like a relief appearance," Darnell said. "As a starter I usually stick with the fastball and changeup and let it ride out for four to five innings without using my curve ball and my slider. But if I'm relieving and I have a chance to punch a guy out, I can bury the slider right there."
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Darnell lowered his earned run average to 3.86 in the process, but he's not on the 40-man roster after being outrighted during the offseason. He knows it'll be difficult to make the team, as he's one of several non-roster lefties competing for a spot, along with Fernando Abad, Buddy Boshers and Dan Runzler. Taylor Rogers and Ryan O'Rourke are the two lefties still in camp who are on the 40-man roster.
"At this point I'm just going out there and trying to get people out," Darnell said. "I know there are a bunch of good lefties here, and every one of them has pitched well. So I'm just trying to get outs, and whatever they want me to do, send me that way and I'll do it."
Darnell saw limited action for the Twins in 2014, posting a 7.13 ERA while making four starts and three relief appearances. He was brought up again last season as a September callup but never pitched after coming down with pneumonia in early September.
Darnell mostly pitched in relief last year at Triple-A Rochester, with a 3.36 ERA and 66 strikeouts in 77 2/3 innings, but he finished the season in the rotation, posting a 0.83 ERA over his final five starts to earn the callup to the Majors, where he would have pitched in relief had he been able.
So the Twins are giving him a look this spring, and he impressed bench coach Joe Vavra, who served as manager with Paul Molitor making the trip to Clearwater for Minnesota's split-squad game against the Phillies, a 7-5 win.
"He set the tone," Vavra said. "He worked quick and got results right away. It was a respectable lineup, so it was good to see young Darnell come through in his first start."
Rhett Bollinger is a reporter for MLB.com. Read his blog, Bollinger Beat, follow him on Twitter @RhettBollinger and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.