Alexander Mattison has always dreamed about stepping onto an NFL field.

When he got the chance, he took full advantage.

The rookie running back started in the Vikings 34-25 defeat of the Saints, and he found his way into the end zone on the first drive.

After an officials' review determined that Adam Thielen was down at the 1-yard line, Vikings quarterback Kirk Cousins ran a play-action fake and targeted an uncovered Mattison in the corner of the end zone.

"It's just one of those plays that we drew up, and every time we ran it in practice, it was that same type of look," Mattison said after the game. "So as soon as I saw the safety kind of bite down a little bit, I knew I'd be open. Kirk put a great ball on me, and then I just finished the catch."

The 21-year-old said he won't take the moment for granted.

"[I] don't take it lightly. Because as Coach told me, 'It's not easy to score in this league,' " Mattison said. "So it was a great feeling."

Asked if he was nervous to make his NFL debut, he responded, "not really," taking the evening in stride.

"I've been working for this my whole life," Mattison said. "You've got butterflies like you do every game. If you don't have those, then something might be wrong with you. But I tried to put that aside and just go out there and do my job every play."

In addition to the reception, Mattison finished the night with nine carries for 30 yards.

Vikings Head Coach Mike Zimmer appreciated the running back's first outing.

"He ran hard, he caught the ball," Zimmer said. "They kind of bottled up the run a little bit early, but when you stick to it and you create some things off the [pass play], then typically those things start to open up."

Zimmer was asked by media members why Mattison started in place of Dalvin Cook. He explained that he didn't play Cook because he "didn't want to put him out here on the turf" of the Superdome.

Mattison wasn't the only Vikings rookie to make the evening's highlights.

Seventh-round draft pick Bisi Johnson made catches of 17 and 18 yards, respectively, from Sean Mannion in the second quarter, including an impressive touchdown catch on third-and-4 over the top of Saints cornerback Patrick Robinson.

Cousins called it a "unique feeling" to watch the play from the sideline.

"It was great for me to have that perspective," Cousins said. "Great catch by him, and then also Sean to be able to stand in there and take that hit as he was throwing it, that's not easy to do. He threw it with great trust that [Bisi] would come down with it, and he did.

"To convert a third down was also important," Cousins added. "Lot of good things happening on that play."

Johnson said the feeling was "amazing" and laughed that he was "in shock" before breaking into a celebration.

"It was a double move, and I saw that he was way off, so I figured that I had to sell it hard," Johnson said of the play. "I kind of stopped in the middle of the route and then just took off, and Sean gave me a chance. It was good."

The score marked the second of the night from former Mountain West players.

Boise State standout Mattison said he had earlier joked with Johnson – a former rival at Colorado State – about making a splash in their first game.

"I talked to Bisi before the game … I told him, 'We've got to do something for the Mountain West,' so that was awesome to see him get in there and score," Mattison said.

Fast forward to late in the third quarter, and rookie fullback Khari Blasingame also got his chance in the limelight.

Vikings quarterback Kyle Sloter faked a handoff to Mike Boone before arcing a pass to Blasingame, who made the catch and backed into the end zone.

"Khari, he works so hard; he deserves it," Mattison said. "That was awesome."

Johnson reacted to three of Minnesota's four offensive touchdowns being scored by rookies:

"That's crazy. It's good," Johnson said. "These coaches are giving all of us an opportunity. We were in there early, and I think we really showed up."

Vikings tight end Irv Smith, Jr., whom the Vikings drafted in the second round, celebrated his 21st birthday with three catches for – ironically – 21 yards.

And he may not be a rookie, but second-year running back Mike Boone added to the success of Minnesota's running back room, rumbling 64 yards in the fourth quarter for the final score of the night.

Zimmer complemented the talent of the group, and Mattison said it's "exciting" to be part of it.

"It's nothing but love and brotherhood in that room, and just to see the performance that we were able to put out there, it's showing that our hard work is paying off," Mattison said. "We've just got more to do, and we'll continue to grow and get better."