He played college football for the Auburn Tigers and was selected by the Detroit Lions in the second round of the 2018 NFL draft.

[5] As a freshman at Auburn in 2015, Johnson was a backup to future NFL starter Peyton Barber and Jovon Robinson, and never reached 10 rushes or 40 rushing yards in a game, though he was used occasionally as a kick returner and reached 161 all-purpose yards against Kentucky.

[7] As a sophomore in 2016, he began the season starting six games, before becoming the backup to Kamryn Pettway, recording 895 rushing yards on 182 carries and 11 touchdowns.

[6] As a junior in 2017, Johnson became the Tigers' dominant rusher, with almost three times as many carries as any other player on the team.

However, the #2 Tigers lost the Southeastern Conference (SEC) Championship in a rematch with Georgia, where Johnson was limited to 44 yards.

[11] In the subsequent Peach Bowl, Johnson had 71 rushing yards and a touchdown in the loss to #10 Central Florida.

[13] On January 2, 2018, Johnson announced that he would forgo his senior year and enter the 2018 NFL draft.

[18] He made his NFL debut in the season opener against the New York Jets on Monday Night Football.

[20] The performance won him the starting role over LeGarrette Blount, which he used to score his first NFL touchdown the following week against the Dallas Cowboys though he was limited to just nine carries.

[25] In the Week 11 win over the Carolina Panthers, Johnson had 87 yards and a rushing touchdown before spraining his left knee in the third quarter and missed the next four games.