KANSAS CITY -- The single most determining factor for fan favorite Rusty Kuntz deciding to return to the Royals' coaching staff: new manager Mike Matheny.

Sure, Kuntz had to be confident the issue with his eyes that caused him to leave the coaching staff late in 2017 had been resolved. And he said his eyes are fine now.

As a special assistant to general manager Dayton Moore the past two years, Kuntz was on the road frequently. And that allowed him to really get to know Matheny, who had a similar role as a special advisor to Moore.

“I got to spend the summer with Mike, and he’s just a great guy, just wonderful to be around,” Kuntz told MLB.com. “He’s a smart baseball guy. Everywhere we went this summer, to our affiliates, players just gravitated toward him. He has all kinds of positive energy. And he’s just a baseball guy.

“I kept kind of looking for a crack in that personality, and it was never there.”

Fate stepped in as Moore and his staff approached first-base coach Mitch Maier about a possible move to the front office as director of baseball operations.

“Once Mitch got the opportunity to move to the front office, that created a void,” Kuntz said. “Mike came to me and asked me if I would be interested, and the more I thought about it, I thought it would be great working on that staff with Vance [Wilson] and LC [Larry Carter] and Pedro [Grifol]. The time was right to come back.”

Kuntz is regarded throughout the industry as an outfielder guru, helping transform Alex Gordon from a third baseman to a seven-time American League Gold Glove Award winner in left. Kuntz also helped elevate Lorenzo Cain into one of the top defensive center fielders in baseball.

Kuntz again will have the task of helping improve Jorge Soler’s skills in right field.

“Pedro says Jorge is in super shape down in Miami, and he’s really anxious to play right field,” Kuntz said. “And that’s really a plus for us because there are going to be days we’ll need [Salvador Perez] to DH, so we’ll need Jorge to go to right field. And he really wants to do that and get better. And it’s my job to make him better. I know Jorge can’t wait to get started down in Arizona.”

As for the issues with his eyes, Kuntz said that after cataract surgery in 2017, he had trouble healing and adjusting in his right eye. He described it as trying to see while looking through a water glass.

It became an issue when former Royal Mike Moustakas hooked a liner late in 2017 toward the first-base coaching box: Kuntz never saw it and nearly got hit.

“It’s better now,” Kuntz said. “I’ve got one good one and one really good one now.

“And besides, as Mitch pointed out, Moose is with Cincinnati now, so I don’t have to worry about him hooking any liners at me.”