In Mims first three seasons, he rushed 291 times for 1,203 yards and 13 touchdowns, while also bringing in 45 passes for 521 yards and three touchdowns.[4] However, in 2021 Mims would breakout. Mims had a breakout game in week nine, where he rushed for 186 yards and two touchdowns to help upset #21 San Diego State and hand them their first loss of the year, beating them 30–20.[5] Mims also had a stellar performance in the team's bowl game where he rushed for 165 yards and two touchdowns along with hauling in five passes for 71 yards and a touchdown.[6][7] For his performance on the game he was named the New Mexico Bowl Offensive MVP.[8] Mims finished the 2021 season with 710 yards and six touchdowns while also racking up 25 receptions for 324 yards and four touchdowns.[9] Mims opened up the season hot, having a standout game in week two against Oregon State, where he rushed 21 times for 122 yards and two touchdowns. However the Bulldogs would fall 35-32 as Oregon State fullback Jack Colletto scored a game winning touchdown.[10] In week seven Mims had his best regular season performance as he would have 26 carries for 165 yards and a touchdown, as Mims helped the Bulldogs beat New Mexico 41–9.[11] Then four weeks later in Week 11, Mims had another great performance rushing 19 times for 156 yards and a touchdown as he helped lead Fresno State to another win beating Nevada 41–14.[12] Just a week later in Fresno State's season finale Mims rushed for three touchdowns to help beat Wyoming 30–0.[13][14] In the Mountain West Conference Football Championship Game, Mims had an excellent game running for 83 yards and two touchdowns, as he helped the Bulldogs beat Boise State, 28–16.[15][16] In Fresno State's bowl game, Mims had the best game of his career rushing for 205 yards and two touchdowns, as Fresno State defeated Washington State 29–6 to win the LA Bowl.[17][18] For his performance on the game he was named the LA Bowl offensive MVP.[19] Mims finished the year with his best year ever, carrying the ball 261 times for 1,372 yards and 18 touchdowns, while also bringing in 21 receptions for 126 yards and a touchdown.[20] For his performance on the year he was named First Team All Mountain West.[21]
Mims finished his career in the Fresno State record books multiple times ending up 5th in all purpose yards, 4th all time in receptions by a running back, 4th all time in rushing yards, tied for 3rd all time in rushing touchdowns, tied for 3rd all time in 150 yard rushing games, 2nd all time in rushing attempts, and 2nd all time scoring leader.[22]
On August 30, 2023, Mims was signed to the practice squad of the New Orleans Saints.[27] He was promoted to the active roster on October 14 and made his regular season debut in the Saints 20–13 loss to the Houston Texans, where he recorded one tackle in a special teams role.[28] Mims was waived five days later after running back Jamaal Williams was activated from injured reserve.[29][30] On October 23, Mims again signed to the Saints practice squad.[31] Following the end of the 2023 regular season, the Saints signed him to a reserve/future contract on January 8, 2024.[32]
On October 26, 2024, Mims was waived by the Saints and re-signed to the practice squad.[33] He was promoted to the active roster on November 2.[34]