KANSAS CITY -- While rookie starters Bailey Ober and Joe Ryan had relatively smooth transitions to the big league level this season, that final step from Triple-A to the Majors is still a tough one -- and Griffin Jax wore many of those lumps in his extended look with the Twins in the final two-plus months of the season.

Still, throughout that time, he described this as an unprecedented opportunity that not many rookies get in their transition to the big leagues.

In a largely results-driven industry, Jax had the chance to settle into a routine regardless of his stat line on any given night, learn from those setbacks and know that he’d have the chance to build on it five games later. And all that work culminated in one of his finest efforts of the season with five scoreless innings of one-hit ball in the Twins’ 4-0 series-evening victory over the Royals on Saturday night at Kauffman Stadium.

“To come up here and get consistent starts under this great organization and leadership in this clubhouse, for me, it was huge,” Jax said. “It was a confidence boost just to be able to walk in every single day knowing that I’m still going to get the ball every five days. ... It helps boost confidence moving into the offseason.”

Among Jax’s 18 appearances for Minnesota this season, including 14 starts, it marked the first in which he didn’t allow a run. It was his first outing since July 30 in which he didn’t allow a home run, a span of 10 starts in which an opponent went deep.

“I'd never really struggled as much as I had, in my entire career, until these last few starts,” Jax said. “The good, successful starts I've had up here are what I'm typically used to. … If I'm going to be struggling anywhere, I'd rather be struggling here. It just helps me learn.”

And after his difficulties throughout the last two months, leading to a 6.37 ERA and 23 homers allowed in 18 games this season, he again flashed the form that saw him yield six earned runs in a four-start stretch in late July and early August against the White Sox (twice), Astros and Cardinals.

The 26-year-old retired the first eight Royals he faced before allowing his only hit, a single through the left side by catcher Cam Gallagher. Though Jax walked a pair in the fourth inning, no runner advanced beyond first base on his watch before the bullpen finished off the Twins’ ninth shutout of the season. Minnesota got a pair of RBIs from Luis Arraez, a run-scoring single from Mitch Garver and Josh Donaldson’s 26th homer to support the pitching effort.

“To step in as a young player and start, and get these starts, that shot doesn't come around every day,” manager Rocco Baldelli said. “But in addition to getting the outings, you're also going to learn what plays at the big league level and what needs to be adjusted. Most guys don't get the opportunity to just kind of figure that out on the fly over the course of half the season.”

As part of those adjustments, Jax got to work extensively with pitching coach Wes Johnson on the slider that could continue to serve as an important part of his success moving into next season. There was added emphasis on the curveball on Saturday as well that helps to round out his arsenal, particularly on days during which he doesn’t have his slider working -- of which he had a few earlier this season.

The Twins will need all the help they can get for their 2022 rotation. Ober and Ryan appear to be the surest candidates ahead of a depth group that could also include Jax, Randy Dobnak, Devin Smeltzer, Lewis Thorpe, Jhoan Duran, Josh Winder and Drew Strotman in addition to any offseason acquisitions.

Minnesota has seen the potential that led to Jax’s 10-strikeout start against the White Sox in mid-August, capping that successful string of starts. The hope is that he can take advantage of this unique experience in his offseason work to reach that level more often.

“I think he and Wes had a ton of conversation, and we saw it come to fruition in the last start of the season,” Baldelli said. “We’ve seen this from him at different points in the year, and to see him kind of build towards this going into the offseason, [it’s] a great last outing.”