SURPRISE, Ariz. -- Sitting in his office early Friday morning, Royals manager Ned Yost suggested it was way too early to begin formulating his rotation for 2018.
"We're just observing at this point," Yost said. "That's all."
Yet it would seem obvious that Yost's front four will be veterans Danny Duffy, Ian Kennedy, Jason Hammel and Nathan Karns.
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And the Royals will be keeping a close eye on the 30-year-old Karns, acquired prior to last season from the Mariners for Jarrod Dyson. Karns was lights out last May as a starter before he went on the disabled list and ultimately underwent thoracic outlet syndrome surgery, a procedure that relieves nerve tension in the chest and shoulder area by removing a part of the upper ribs.
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Karns reports all systems are go early in camp. He threw his fourth bullpen session Friday.
"We worked hard to come in here with no restrictions," Karns said. "I've had no setbacks or hiccups. I'm as normal as we can be."
Karns credits an offseason program of throwing a football to re-teach his body the proper throwing mechanics again.
"When you throw a football you have to be mechanically sound to throw a spiral that far," Karns said. "It forced me to use my lower body better. So far so good."

Karns said he played football growing up but wasn't a quarterback. He has enjoyed tossing the football, however.
"The reason we had surgery was I had added tension in my nerves," he said. "And throwing a football keeps me short in my throwing motion. It's been like using a clicker. You keep the number of throws down early to start with and you build up. You throw 10-15 yards, just getting it there and making your arm and shoulder function the way it should be. I think I'll be doing this every offseason."
The Royals are hoping Karns can return to the form he displayed in May of last season when over four starts he went 2-0 with a 2.01 ERA. During that span he struck out 32 batters over 22 1/3 innings and opponents hit .202 off him.
"So far it's all good," he said. "I've had four bullpens, and I've recovered easily from all of them. I'm not overthrowing at all. Just relaxed and hitting my location."