"There were a lot of good days, but it just didn't work out," Minor said. "I kept getting shut down with shoulder fatigue. ...
"I'd feel great for two or three innings, and then I'd get to four innings and I'd get fatigued. The ball wasn't coming out right and I was feeling sore there. Then afterward, I'd get achy in that area. It was frustrating."
This time around, Minor, 29, will make the transition to the bullpen. From 2010-14, Minor made exactly one appearance out of the bullpen. He knows it will be an adjustment.
"I'm pretty anxious to see how it responds in terms of the bullpen when you're not throwing as many pitches at one time," Minor said. "I don't think you truly recover when you're in the bullpen because you're throwing all the time. But hopefully it will help me build strength."
Minor said he was pain free all offseason as he went through his throwing and conditioning program.
"It's been good," Minor said. "I feel great right now. Everything has gone smoothly. It's been a good Spring Training so far compared to the last two years. I had the surgery in 2015 right after Spring Training. Last year, I was off doing my own thing still recovering and not really with the guys."
Royals manager Ned Yost said he hopes Minor's velocity, normally around 91-93 mph, might tick upward working out of the bullpen, as it did for other converted starters such as Wade Davis and Luke Hochevar.
"I've never been a bullpen guy so I don't know if that will happen," Minor said. "But I do remember even last year my velocity would be higher the first two innings or so. I don't know if it will be consistently like that but we're hopeful."
Losing his shot at the rotation isn't a big concern, Minor said.
"Not really," he said. "I just want to pitch. I just want to get back to the big leagues and pitch. I'm excited about it."
Jeffrey Flanagan has covered the Royals since 1991, and for MLB.com since 2015. Follow him on Twitter @FlannyMLB. This story was not subject to the approval of Major League Baseball or its clubs.