[2] Jackson was named the South Carolina Basketball Gatorade Player of the Year after averaging 22.1 points, 10.9 rebounds, and 2.3 blocks per game and leading the Blazers to a second straight state title in his junior season.

On August 31, 2023, he signed a two-way contract with the Grizzlies, splitting time with their NBA G League affiliate, the Memphis Hustle.

[18][19] On March 10, Jackson made his starting debut for the Grizzlies against the Oklahoma City Thunder, where he would score 30 points in a 124–93 loss.

[20] On March 20, Jackson scored 35 points with seven three-point shots made in a 137–116 loss to the Golden State Warriors, becoming the youngest player in NBA history to make seven threes in a game.

[23] On August 27, Jackson suffered a broken right foot and underwent surgery on September 4, delaying his start to the season by at least three months.