Jermar Jefferson broke out as a true freshman in 2018 as he garnered Freshman All-American, Pac-12 Freshman of the Year, and honorable mention all-conference honors with 1,380 rushing yards and 12 scores on 239 carries (5.8 per attempt). Jefferson also caught 25 passes for 147 yards that season, displaying his competence as a receiver. The following season, an ankle injury stunted his sophomore campaign limiting him to six starts in nine games played as he compiled 142 carries, 685 yards, and eight touchdowns. Jefferson rebounded in 2020, earning first-team All-Pac-12 accolades by ranking fourth in the FBS with 143 rushing yards per game and ninth with 159.5 all-purpose yards per game. He did miss one game due to COVID-19 protocols.