Fenwick had an outstanding collegiate debut as he rushed for 112 yards and a touchdown, as he helped the Gamecocks beat Chattanooga.[5][6] Fenwick finished the 2018 season with 115 yards and a touchdown over a span of two games.[7] In week ten of the 2019 season, Fenwick had another great performance rushing for 102 yards in a win over Vanderbilt.[8][9] Fenwick finished the 2019 season playing two games, while rushing for 111 yards.[10] Fenwick opened the 2020 season strong, as in week five he rushed for 32 yards, and bring in five receptions for 24 yards, but South Carolina would fall to the Florida Gators.[11][12] In week seven, Fenwick again had a good game, rushing for 68 yards as he helped the Gamecocks beat Auburn.[13][14] In the next game in week eight, Fenwick rushed for 49 yards, and caught two passes for 19 yards, but South Carolina would lose to LSU.[15] Two weeks later, Fenwick had another good performance rushing for 82 yards and bringing in one reception for four yards, but the Gamecocks would lose 59–42 against Ole Miss.[16] In the following week, Fenwick would have a disappointing performance rushing for only seven yards but he would score a touchdown, but the Gamecocks would again lose, this time against Missouri.[17][18] Fenwick would finish the season with 297 yards and one touchdown, while also bringing in 14 receptions for 108 yards.[19] After the conclusion of the 2020 season, Fenwick announced that he had entered the transfer portal.[20][21]
Fenwick announced that he had decided to transfer to Oregon State.[22][23] Fenwick would have a good performance in week three, where he rushed for 59 yards and his first touchdown as a Beaver, as he would help Oregon State beat Idaho 42–0.[24][25] Three weeks later, Fenwick would have another career game rushing for 127 yards and two touchdowns, but Oregon State would fall short to Washington State.[26][27] In week nine, Fenwick had a good game rushing for 48 yards and a touchdown, but it would not be enough as California beat the Beavers 39–25.[28] Fenwick would finish the year with 448 yards and four touchdowns, while also hauling in four receptions for 14 yards in his first season with Oregon State.[29] In the preseason, Fenwick was named to the Doak Walker Award watch list, which is awarded to the nation's best running back.[30][31] Fenwick would open up the season with a decent performance, rushing for 39 yards and a touchdown, as he would help the Beavers win their season oppener against Boise State.[32][33] In the next game, in week two, Fenwick would have a great performance rushing for 102 yards and a touchdown as Oregon State outlasted Fresno State 35–32.[34][35] Fenwick would keep his hot start going, as in week three he rushed for 63 yards and a touchdown, as the Beavers dominated Montana State 68–28.[36][37] Fenwick would slow down in week four, rushing for only 29 yards but punched in another touchdown, but Oregon State would lose 17-14 versus USC.[38][39] In week ten, Fenwick had a pretty good performance rushing for 37 yards and two touchdowns, but his performance would not be enough as Oregon State lost to Washington 24–21.[40][41] In the Beavers season finale against hated rival Oregon, Fenwick had another good performance rushing for 53 yards and a touchdown, as the Beavers upset Oregon 38–34.[42] In the team's bowl game, Fenwick had an amazing performance rushing for 107 yards, as Oregon State dominated Florida 30–3, to win their bowl game.[43][44] Fenwick finished the season with 553 rushing yards and seven touchdowns, while also catching four passes for 15 yards.[45] Fenwick is in line to be a major contributor for the Beavers in the 2023 season.[46]
