KANSAS CITY – Royals manager Mike Matheny continually pumped up the prospects of right-hander Jesse Hahn during Spring Training.

Many fans and media members simply didn't listen.

Matheny turned out to be completely right that Hahn, once he got his signature pitch, the curveball, back and effective, would be a huge factor for the Royals.

The Royals saw the return of Hahn in 2020. He entered Saturday's game with a team-best 0.55 ERA in 17 outings. And with the uncertainty regarding the future of closer Greg Holland, who is a pending free-agent, Hahn very well could be the closer for Kansas City in 2021.

Hahn, 31, is 2-for-2 in save opportunities this season.

A former starter with the Padres and A's before the Royals acquired him in the Brandon Moss trade in January of 2018, Hahn has slid into a reliever's role in Kansas City with great confidence. He has a remarkable 0.673 WHIP, and he has a strikeout ratio of 8.8 per nine innings.

It has been a long journey for Hahn since coming to Kansas City. He has battled numerous arm injuries and didn't pitch at all in the big leagues in 2018. Hahn came up for six games at the end of '19, mainly to prove to himself he could still be a factor in the big leagues.

But it was this spring when Hahn finally began to feel completely healthy. Matheny noticed it immediately.

"No question he fits into the bullpen plans [for 2021]," Matheny said. "It was nice having someone with the stuff we saw. But also, he has been around a little more, in terms of experience, and that will be a big factor next season, too."

Hahn simply is relieved he was able to play a significant role this year. Aside from the injuries, Hahn’s 2020 season also had personal obstacles. His mother unexpectedly died in late July. And Hahn became a father for this first time a few weeks later.

"It's kind of been a rollercoaster for me this season," Hahn said. "I try to be the same guy in the clubhouse. I knew I had to come in and perform well every single day this year. I try to be like [Alex Gordon]. Everyone tries to be like Gordo, just go out there and do my job."

Hahn has adjusted to life in the bullpen, and he said he loves it.

"For me, it has been great," Hahn said. "There's a lot of adrenaline. I'm someone with a quick tempo, so I've had to learn to slow myself down, step off the mound and take a deep breath. After I threw a couple balls [Friday night], I stepped back, grabbed the rosin bag and took a deep breath. It's good for me."

The Royals may be looking at Hahn as a potential closer now, and he certainly has the stuff -- a mid-90s fastball with a knee-buckling curve.

"Absolutely, I love [the bullpen]," Hahn said. "I feel healthy again. I am looking forward to this offseason and pitching. And I can do stuff on the mound this offseason, stuff I couldn't do the last two years because it was just about getting healthy. It's exciting going into an offseason healthy.

"I love the bullpen. I've adjusted to it. I have a good routine now."