As a true freshman at Louisiana in 2020, Lacy played in 11 games and had 28 receptions for 364 yards and four touchdowns.[3] In 2021, he played in 13 games and had 22 receptions for 304 yards and six touchdowns.[4] After the season he transferred to Louisiana State University (LSU).[5] He started two of 14 games his first year at LSU in 2022, recording 24 receptions for 268 yards.[6] As the third receiver behind Malik Nabers and Brian Thomas Jr. in 2023, Lacy started 10 of 13 games and had 30 receptions for 558 yards and seven touchdowns. He returned to LSU for the 2024 season.[7]