The Cardinals took a chance on safety Tyrann Mathieu in 2013 and Mathieu has delivered a huge reward for the risk.

INDIANAPOLIS -- Dorial Green-Beckham stood on a podium at the NFL Scouting combine Thursday and admitted he was nervous.

A lengthy list of off-field issues have dropped the former Missouri wideout down the NFL draft board – Green-Beckham is a top-5 talent projected to go late in the first round – and it was open season for reporters to question him about those transgressions.

Green-Beckham was contrite about his past, and said he's intent on showing NFL teams that the problems are behind him.

"All the decisions I made, I wish I could take them back," Green-Beckham said. "I was young. I made mistakes."

If Green-Beckham thought his media session was tough, wait until the teams get to him. There's a huge risk-reward component to drafting an elite talent with character concerns, and organizations are hellbent on a thorough dissection. They can set up formal 15-minute interviews here at the combine, but that's just the start.

"In 15 minutes, it's hard," Cardinals coach Bruce Arians said. "They're programmed to answer the right questions. The big thing is to get another chance to stun them with questions they're not programmed to answer. You get a feel for a guy. Does he truly have passion? Does he really want to do the right thing?"

The scenario pops up multiple times per year. The Cardinals identified safety Tyrann Mathieu as a player to take a chance on back in 2013. Mathieu was a Heisman finalist as a sophomore at LSU but was dismissed from the team before his junior year after failing multiple drug tests.

Cardinals cornerback Patrick Peterson gave Mathieu, a former college teammate, a ringing endorsement leading up to the draft, which helped in the front office's evaluation. Mathieu entered the draft after sitting out an entire season – something Green-Beckham will do as well – and the Cards took him in the third round.

It's been an unquestioned success, as Mathieu has made an impact on the field and stayed squeaky clean off it. On Wednesday, General Manager Steve Keim called Mathieu one of the leaders of the locker room. During the interview stage, Arians and Keim felt strongly that he was worth the risk.

"He was genuinely passionate about the game," Arians said. "Giving up the game killed him. You could see it in him. We

also knew we had a great support system, with Patrick and drafting (LSU teammate) Kevin (Minter) with him. We knew he'd be successful and he's done a fantastic job."

The jury is still out on Green-Beckham, who not only had multiple marijuana-related incidents in college but an allegation that he forced his way into an apartment looking for his girlfriend and pushed a woman down stairs. No charges were ever filed, but it was the last straw as Missouri dismissed him from the team. Green-Beckham ended up at Oklahoma, but had to sit out this season as a transfer and never played for the Sooners.

There is a heightened sensitivity regarding domestic violence in the NFL, so any team that chooses Green-Beckham will come under scrutiny.

 "I know the commissioner has done a good job trying to clean up the league," Cardinals general manager Steve Keim said. "That's why this process is so important, to get to know these kids as people."

Green-Beckham could go somewhere in the 20s, and if he does, he would join other talented but mercurial wideouts taken in that range. Randy Moss dropped to the Vikings at No. 21 in 1998, while Dez Bryant went No. 24 to the Cowboys in 2010. Both have had stellar NFL careers, but not without their share of controversy.

Green-Beckham pledges to live up to his billing on the field – he was the top recruit in the nation coming out of high school – but avoid the traps off it.

"I know what's at stake," Green-Beckham said. "I know what type of person I am, and I understand what the NFL is looking from me as a person. I just want them to know I'm going to go out there and give my all, show everybody what I'm capable of doing, and just focus on being the best player I can be."

Teams will be skeptical, but talented players are always going to pique the interest of front offices. Green-Beckham could turn his life around, dominate on the field and be a huge coup. He could struggle and add toxicity to a locker room. He could land somewhere in between.

It's why the combine and the ensuing weeks are so critical, as teams hope to make the right call.

"There are a lot of unknowns," 49ers GM Trent Baalke said. "There's a risk-reward to this business, and that's not going to change."