EDEN PRAIRIE, Minn. —Like most rookies, Tre Roberson didn't know what number he'd get assigned when he showed up to the Vikings three-day rookie tryout in May.
Unlike the other rookies, however, Roberson also didn't know what position he'd be playing.
"I didn't know I was playing cornerback until I came here for the rookie tryout," Roberson said with a smile. "There was a No. 21 jersey in my locker, so I asked what position I was playing.
"They said that's a corner number," he added. "I guess I was playing corner, so I wanted to go out and do the best I could."
Although Roberson now wears No. 36, he's remained at the position more than three months later.
It's been quite the journey for Roberson, an undrafted free agent out of Illinois State, the alma mater of Vikings Head Coach Mike Zimmer.
The 23-year-old began his career at Indiana in 2011, where he played quarterback for two seasons while redshirting another. Roberson then transferred to Illinois State, where he was the Redbirds' signal caller for two more seasons.
Roberson made an immediate impact at Illinois State and was the Missouri Valley Football Conference Newcomer of the Year in 2014.
He showcased his offensive ability as a dual-threat quarterback with Illinois State, totaling 7,252 yards and 70 touchdowns in two seasons.
Yet as Roberson and his agent prepped for the draft, they kept their options open and didn't campaign him as just a quarterback.
"We decided we were going to go (into the draft) as an athlete," Roberson said. "Whatever anyone wants us to be…a quarterback, wide receiver, (defensive back), whatever…we were going to take that chance and give everything we had."
That led to Roberson landing in Minnesota, thrown into a position he said he hasn't played since school-yard ball as an elementary student.
Roberson is raw at the position, but his athletic ability and eagerness to learn has impressed a handful of coaches, including Zimmer.
"He does some things that are very natural for a guy that has never played corner before, just watching him backpedal and break," Zimmer said during training camp. "He has still got tons to learn, but as far as athletically – when you're used to playing quarterback, and now you're backpedaling and trying to learn defensive schemes and coverages – I think he has done really good."
Vikings defensive backs coach Jerry Gray said there have been a handful of times where Roberson makes a play that a longtime cornerback would.
"That means he's paying attention," Gray said. "He's paying attention to the guy that's in front of him, in the meeting rooms … the only thing that's holding him back is that his body has really never done the work to create new habits.
"Everything he's doing is really from a brand-new place," he added.
Roberson said his biggest challenge has been learning Minnesota's defensive concepts while also being thrown into the brand-new position.
The Indiana native has more than held his own at times, especially during training camp and the preseason.
Roberson helped preserve Minnesota's 17-16 win over Cincinnati by defending a late 2-point conversion in the corner of the end zone.
Not many people but Roberson knew that he had broken his right hand — the same hand he used to guard the intended receiver — in the second quarter while covering a punt on special teams.
"It didn't hurt as bad, and I wanted to stay in and show some toughness," Roberson said. "The adrenaline was going. It was a battlefield, so I didn't worry about it.
"I just saw the ball and reacted," he added.
Special teams is another aspect of the game that has been new to Roberson, but he's brought a learner's attitude to those tasks.
"Like a lot of young rookies, he's eager, he's tough," Special Teams Coordinator Mike Priefer said. "He actually broke that hand in the second quarter against Cincinnati and then continued to play. I didn't know that. I found out after the fact.
"Everything is new to him, but he's very eager to learn, and he's worked very hard on his technique and has come a long way since the spring," Priefer added.
Recovering from the hand injury caused Roberson to miss some time, but he has since returned to practice and could play in the Vikings final two preseason games, starting with Sunday's noon (CT) tilt against the Chargers at U.S. Bank Stadium.
Roberson noted he sometimes uses his history as a quarterback to help him out at his new spot. But he he's mainly focused on learning the ins and outs of his new position, one he plans on sticking with for a while.
"I'm a football player," Roberson said. "I love to play and love everything about the game.
"Meetings, practices, anything that has to do with football is all fun," he added.