Jefferson declared for the draft in a video released through The Players' Tribune:
After two strong seasons to begin his collegiate career at Texas, Jefferson reached another level in 2017 by setting a career high with 110 tackles to go along with 10 tackles for loss.
It was apparent from the time of his arrival at Texas that Jefferson had the potential to be a special player; he was named the 2015 Big 12 Defensive Freshman of the Year by virtue of his 61 tackles and 2.5 sacks.
Jefferson followed that up as a sophomore in 2016 with 60 tackles and 6.5 sacks.
While Jefferson has been a defensive stalwart for the Longhorns, team success has been difficult to come by during his tenure.
Texas went 6-6 in 2017 after a pair of 5-7 seasons in 2015 and 2016, both of which resulted in failing to reach a bowl game.
Jefferson wasn't the issue, however, and all signs point to him being among the first linebackers selected in the 2018 NFL draft.
According to Bleacher Report's Matt Miller in his Dec. 15 big board, Jefferson is the No. 3 linebacker in the 2018 class behind only Alabama's Rashaan Evans and Georgia's Roquan Smith.
Miller also rated Jefferson as the best linebacker in terms of pass coverage.
The Mesquite, Texas, native is a rare prospect in that he boasts ideal size at 6'3" and 240 pounds, while also maintaining impressive speed and the ability to hang with running backs and tight ends.
While the predraft process could change things, every indication is that Jefferson is making a smart decision by declaring since he has all the makings of a first-round pick.