Thibodeaux will not play in the Ducks' bowl game, a matchup against No. 16 Oklahoma in the Valero Alamo Bowl on Dec. 29, and instead will begin preparations for the draft, in which he could be selected with the top pick.
ESPN's Mel Kiper Jr. has Thibodeaux rated No. 1 overall in his latest Big Board. Fellow ESPN draft analyst Todd McShay has him as the No. 2-rated prospect in this year's class.
"Thank you for embracing a kid from South Central, Los Angeles and giving me the opportunity to transition into a man ready to take on the world," Thibodeaux wrote as part of a post on social media, in which he thanked "the University of Oregon, the city of Eugene, and Duck Nation for their unwavering support."
The 6-foot-5 Thibodeaux was the Pac-12 defensive freshman of the year in 2019 and a first-team All-Pac-12 selection last year after arriving at Oregon as the No. 1-ranked player in the class of 2019. He played 10 games this season -- an ankle injury slowed him early -- and finished with seven sacks and 49 total tackles.
He is a finalist for the Bednarik Award and Bronco Nagurski Trophy.
Thibodeaux was also at the forefront of players' ability to capitalize on their name, image and likeness. He signed a handful of deals, including one with eBay, another with United Airlines and a six-figure memorabilia deal. Thibodeaux also released an NFT in partnership with Nike founder Phil Knight and sneaker designer Tinker Hatfield that sold for $100 per unit. In September, Thibodeaux launched his own cryptocurrency called $JREAM.
Thibodeaux's early exit came on the same day that Mario Cristobal left Oregon to take the head-coaching position at Miami.
Information from ESPN's Paolo Uggetti was used in this report.