Marcellas Dial attended Woodruff High School in South Carolina. Over his high school career, he earned 3-star recruit ratings from ESPN, 247 Sports and rivals.com. He was not highly recruited out of high school and chose to join Georgia Military College.
Dial tallied 10 tackles and one interception in his first college season with Georgia Military College. In 2020, they did not play a fall season, and following the year, Dial transferred to South Carolina.
Dial's first season with South Carolina was his redshirt sophomore year. He played in all 13 games, making 7 starts at corner. He recorded 33 tackles and 6 pass breakups.
In 2022, Dial played in all 13 games, starting 10 of them. He totaled 45 tackles with a team-leading three interceptions and a team-high 12 pass breakups on the year.
Dial returned for his redshirt senior season in 2023 and started all 12 games. He made 36 tackles including 2.0 tackles for loss and a sack and also logged a team-high 10 pass breakups.