KANSAS CITY, MO. — You never forget your first big-league start, and in Griffin Jax's case, it came at Kauffman Stadium almost exactly three months ago. But Jax may want to substitute the memory of his final start of 2021, on the same Kansas City mound, for that one.

Jax held the Royals to one hit over five innings and didn't give up a run for the first time in his 18 career MLB appearances, and Twins pitchers gave up only three hits in a 4-0 shutout of the Royals.

"In a sense they're all kind of memorable. But it's nice to end on a high note going into the offseason," said Jax, who finishes 2021 with a 4-5 record and a 6.37 ERA in 82 innings. "I'd never really struggled as much as I had, in my entire career, until these last few starts. So if anything, I'm just learning a lot."

And if zero is a nice round number to embrace, 90 is one to avoid, at least for this year's Twins. At 72-89, Minnesota can escape the stigma of becoming the 15th team in franchise history, and sixth in the past 11 seasons, to reach the 90-loss benchmark.

Josh Donaldson smashed a first-inning fastball from Royals lefthander Kris Bubic 435 feet into the fountain behind the seats in left-center, providing all the offense the Twins would need to support the shutout pitching of Jax and relievers Caleb Thielbar, Tyler Duffey and Alexander Colome.

The Twins added single runs in the fourth, fifth and eighth innings, two of them driven in by Luis Arraez. Miguel Sano and Byron Buxton each doubled and scored as the Twins ended their two-game losing streak.

BOXSCORE: Twins 4, Kansas City 0

The finish wasn't without incident, though. The bottom of the ninth inning began with a brief argument between Jake Cave, who had just been called out on a pitch that might or might not have caught the bottom of the zone, and third-base umpire Dan Bellino. Buxton stepped in and backed Cave away to prevent him from being ejected.

And the game ended on a 6-4-3 double play, one of eight such final plays in the majors this year. This one, however, was the only one to come without a runner on first base. Salvador Perez hit a sharp grounder to Andrelton Simmons, who noticed Whit Merrifield straying too far off second base. Simmons whipped the ball to Jorge Polanco, who tagged Merrifield and relayed the ball to Willians Astudillo at first to retire Perez and complete the double play.

"I thought that was just spectacular," Twins manager Rocco Baldelli said. "I have never seen that play out in quite that way. … That's next-level-type stuff."

Ryan Jeffers isn't happy with the .202 batting average, wishes he had reached base more often than his .273 on-base percentage documents. So even though the 2021 season is down to its final hours, he decided to make some changes.

And he's happy with the results. Jeffers hit his 14th home run of the season on Friday, and pronounced himself relatively pleased with his rookie season.

"The numbers don't look great, [but] I've proven I can hit for power at the big-league level," Jeffers said. "Honestly, today we put in a little bit of a newer swing, kind of a 'Why not? Let's mess with it now, get a couple game reps before I go into the offseason.' Can't [judge] from one day, but it seemed to work."

The adjustment, trying to keep his head still — "I get a little drifty sometimes," is how he put it — has the catcher, at 24 only three years removed from college, confident that bigger things are coming.

"I think I can be a 30-home-run-a-year guy. I know that's kind of lofty, but I think that's there," Jeffers said. "Just got to get a little more consistent."

But as a catcher, hitting home runs isn't even the most important part of his game. And Jeffers said he's particularly pleased with the progress he made behind the plate.

"There's a ton defensively, from the gameplan to controlling the pitching staff, that I soaked in and learned this year, and it's going to really help me going forward," Jeffers said. "This year was so much about learning the defensive side of how the big-league game operates. It's different than anything you do in the minor leagues. … Not to use that as an excuse for the lack of offense, but next year I'm going to come in and be in a better spot, hopefully."

Baldelli said after Friday's game he suspected something was physically bothering starter John Gant, after the righthander allowed six runs over four innings.

On Saturday, the Twins decided he was right. Gant was diagnosed with a mild groin strain.

"It happened just as the game was going to start, the last pitch or two in the bullpen. He didn't want to leave us hanging," Baldelli said. "He battled through four innings of work. I'm not shocked to hear he was dealing with something."

Normally, an injury to a starting pitcher in Game 160 wouldn't trigger a roster move, but this worked out conveniently for the Twins. They placed Gant on the injured list, making room to recall lefthander Charlie Barnes from Class AAA St. Paul for the fifth time this season. Barnes will start the season finale on Sunday, Baldelli said.