Oliver, who won the Outland Trophy last season as the nation's best interior lineman, said Monday following the Cougars' first spring practice that he plans to leave after his junior season for the NFL draft.
"I do plan on leaving this year," Oliver told reporters. "It's just the truth. I wish I could stay another year, but it's just my time to go."
A consensus All-American in 2017, Oliver is likely to be regarded as a high pick in the 2019 NFL draft. He is the first underclassman (freshman or sophomore) ever to win the Outland Trophy.
In two seasons, Oliver has amassed 39.5 tackles for loss and is one of the few defensive players that oddsmakers consider to have at least a chance of contending for the Heisman Trophy in 2018.
As a recruit, Oliver was ranked as the No. 4 overall player in the nation in the 2016 ESPN 300. He is the highest-ranked recruit to sign with a Group of 5 program in the modern era of recruiting rankings and is believed to be the only five-star recruit to do so.
"This was a dream of mine coming in," Oliver said. "I knew I was going on a business trip, and whether my business trip was three years or four years it just depended on how early I got on the field and how effective I was."