Thompson is the nephew of former Oklahoma State and St. Louis rams running back David Thompson. After one productive season at Utah State, Darwin decided it was time to see if he was one of the fittest, declaring for the 2019 NFL Draft. Mountain West coaches voted him second-team all-conference in 2018, as he rushed for 1,044 yards and 14 touchdowns (6.8 average) on just 153 carries in 13 games (nine starts). He transferred to USU from Northeastern Oklahoma A&M, where he was a second-team NJCAA All-American and conference Offensive MVP as a sophomore after rushing for 1,391 yards and eight touchdowns. He was also an all-conference performer in his freshman year (1,029 yards, nine touchdowns). Thompson led Jenks High School to a state title as a high school senior, earning honorable mention All-Metro honors from the Tulsa World.