EAGAN — For all the heads Mike Hughes has turned in practice with Minnesota since the Vikings picked him in the first round of the draft , they certainly harbored no plan to play him on 79 percent of the snaps on defense in his first real NFL game.

That’s what happened in his debut, though, thanks to injuries to two fellow cornerbacks. Hughes had an interception return for a touchdown and a team-leading three pass breakups in Minnesota’s 24-16 victory over San Francisco.

“You can kind of tell the way he carries himself that he’s not going to freeze up on the big stage,” free safety Harrison Smith said.

Production like that provided affirmation of general manager Rick Spielman’s decision to ignore needs on the offensive line when Hughes became available with the 30th overall selection.

“We expect him to go out there and do that,” coach Mike Zimmer said. “I mean, that’s why we drafted him. Everybody was complaining about taking that corner. I’m glad we had him.”

Mackensie Alexander’s ankle injury kept him out of the season opener, so Hughes took over as the slot cornerback in the nickel package, a position used more often than the weak side linebacker these days and essentially a starting role. Then cornerback Trae Waynes hurt his knee in the second quarter. With Terence Newman now an assistant coach, Hughes was promoted again to the outside opposite Xavier Rhodes.

“If a player tells you he doesn’t get butterflies before a game, he’s lying. I think it’s natural,” Hughes said. “After the first play, I was good. I settled in and went through my calls and played within the scheme.”

Though all five 49ers kickoffs went for touchbacks, depriving Hughes of any return opportunities, he played the gunner spot on the coverage team and caught a punt to down the ball at the 4-yard line in the first quarter. His time covering kicks was reduced after his defensive responsibility increased, but special teams coordinator Mike Priefer has lauded his ability since he arrived.

“There’s a drive in there that you can see. I’ve been around a lot of young people, and I think he’s one of the guys that really understands what he needs to do to get better,” Priefer said. “He knows he hasn’t arrived yet, even though he was a first-round draft pick. I love his attitude, I love his effort, and he’s improving every day.”

Hughes made some mistakes, of course, on a handful of long gains by the 49ers. He has a lot to learn yet about the game. His attention to detail, however, has stood out to Vikings coaches and players since organized practices began in the spring. So has his athleticism, confidence and instincts. That’s atypical for a rookie.

“Honestly, he plays like he’s been in the league before,” Rhodes said, “and I think years down the road he’s going to be one of the best.”

Hughes wasn’t the only inexperienced player thrust into unexpected action for the Vikings, who despite their status as Super Bowl contender have the NFC’s youngest squad with an average age of 25.47 years on the opening roster.

Backup safety Jayron Kearse replaced Hughes at the nickel back spot. Though he’s been a valuable special teams players over his first two years, Kearse’s only career start as a rookie in 2016 at Chicago was best remembered for a 69-yard run by Bears running back Jordan Howard aided by an awkward overplay by Kearse as he approached in tackling position.

“It was something you couldn’t look past,” Kearse said, “but now I had another opportunity and I just wanted to show I’m not the same player I was.”

The Vikings play at Green Bay on Sunday, when the secondary will have to be as sharp as ever if Packers quarterback Aaron Rodgers plays on his sprained knee . Hughes and Kearse, at least, will be one game better for it.

“Showing that I can get in and cover a slot, showing that I can get in and cover a tight end,” Kearse said, “that was big for me to show the coaches that I can be more than just a special teams player.”