Barnes redshirted as a freshman at Kansas State in 2015. As a redshirt freshman in 2016, Barnes broke out and rushed for 442 yards and six touchdowns on 56 carries in 11 games. Barnes' break out continued as a redshirt sophomore in 2017. He started all 13 of Kansas State's games and rushed for 819 yards and seven touchdowns on 146 carries along with catching five passes for 29 yards and throwing a touchdown pass. However, Barnes suffered ankle pain throughout the season which limited his workload. In 2018, as a redshirt junior, Barnes was the
Big 12 Conference's leading rusher with 1,355 yards with 12 touchdowns on 256 carries in 12 games. He was named to the All-Big 12 football team. After the season, Barnes decided to forego his senior year to pursue a career in the NFL. ==Professional career==