In week three of the 2021 season, McCaskill rushed for 118 yards and three touchdowns in a win over Grambling State.[4] He finished the season with 961 rushing yards and 16 touchdowns while also hauling in 113 receiving yards and two touchdowns. His 16 rushing touchdowns set a Houston freshman record.[5] For his performance, he was named the American Athletic Conference Rookie of the Year, and second-team all-conference.[6][7] Prior to the 2022 season, McCaskill suffered a season-ending torn ACL.[8] After not playing in the 2022 season, McCaskill entered his name into the NCAA transfer portal.[9]
Colorado
McCaskill transferred to play for the Colorado Buffaloes.[10] During the 2023 season, he rushed just 14 times for 59 yards in four games in order to preserve his redshirt and use it to redshirt in 2023.[11] After the season, McCaskill entered his name into the NCAA transfer portal for the second time.[12]