As a true freshman at LSU in 2018, Chase played in all 13 games and made seven starts. He finished the season with 23 receptions for 313 yards and three touchdowns. He returned as a starter in 2019, and that year led the FBS in receiving yards with 1,780 yards on 84 catches (21.2 avg) and receiving touchdowns. His 20 receiving touchdowns set a Southeastern Conference (SEC) record. Six times he eclipsed the 100 yard mark and an additional three times he eclipsed 200 receiving yards in a game mark, including a College Football Playoff championship game record 221 yards against Clemson. At the end of the regular season, Chase was awarded the Fred Biletnikoff Award as the best receiver in college football. He was also unanimously recognized as an All-American.