His decision-making, though, would probably be ranked lower after the potential top-5 pick in the upcoming draft revealed Wednesday to NFL.com that he had failed a drug test at the NFL scouting combine in February.
"I blame myself," Gregory said in revealing he tested positive for marijuana. "And I know it sounds cliché, but there's really no one else I can blame."
The 22-year-old prospect, who tested positive for the drug twice while at Nebraska, learned he failed a drug test at the combine when a letter arrived at his family's home. Gregory, anticipating an invitation to the NFL draft in May, asked his father to open the letter.
It wasn't the news he hoped for.
"Obviously this is new news -- that I failed the test at the combine -- but the fact that I've smoked in the past isn't a mystery," Gregory said. "I've had conversations with coaches. I believe we all have an understanding of why I did it. But I feel like I'm improving. I know I am."
Gregory said he had not smoked marijuana since December, but because of excessive use at Nebraska, his THC levels were so elevated they caused him to test positive for the drug.
Gregory received First-Team All Big-Ten honors in back-to-back seasons with Nebraska after transferring from Arizona Western Community College. He had been recruited by Purdue but couldn't qualify academically.
Last season, Gregory led the Cornhuskers with seven sacks and had 54 tackles, 10 for a loss, despite missing two games with a knee injury. He missed the 2012 season because of a broken leg.
The fear now for the young pass rusher is his draft stock just took a big hit.
"Am I worried? Yeah, I'm worried," Gregory said. "At the same time, I'm confident. I know I'm going to be all right in the end."
Gregory will now begin his NFL career in Stage 1 of the league's substance abuse program, meaning he'll be tested more frequently, and is a step closer to being suspended or even banned from the league than his fellow rookies.
"[Marijuana] could end my career," he said. "This incident right now is a step toward ending my career. The last thing I want to do is fail another drug test and be out of the league."