College of Coastal Georgia

2024-25

Mannie appeared in limited action during his campaign at Charleston Southern. His season-high eight points came against LSU on November 19, when he connected on two field goals, including two three-pointers, and converted two free throws. Mannie logged a season-high seventeen minutes against Georgia Tech on November 27, recording three rebounds and one steal while shooting two-of-four from the field. Mannie also dished out a season-high three assists against Morris on November 11. Throughout his limited appearances, Mannie demonstrated his ability to contribute when called upon, particularly as a perimeter shooter and playmaker.

2023-24

Mannie appeared in twenty-four games and earned two starting assignments at Georgia Southern. Mannie averaged 5.3 points and 1.1 rebounds per game while shooting 38.0 percent from the floor and 32.3 percent from three-point range. At the free-throw line, Mannie converted at an impressive 81.0 percent clip. Mannie scored in double figures seven times throughout the season, with his best performance coming against East Carolina on November 20, when he erupted for a career-high seventeen points on five-of-seven shooting while also grabbing three rebounds. Mannie averaged 10.0 points per game at the TowneBank Holiday Classic, including a thirteen-point performance against Northeastern on November 21. Mannie led the Eagles with thirteen points at No. 12 Tennessee on December 12 and made a career-best four three-pointers while scoring twelve against Southern Miss on December 30. Mannie sank a career-high six field goals and scored fifteen points at South Alabama on February 7 while logging a season-high twenty-seven minutes. His ability to score efficiently and provide instant offense off the bench made him a valuable weapon for the Eagles.

2022-23

Mannie played in eighteen contests and averaged 2.4 points per game at Georgia Southern. Mannie shot 71.0 percent from the free-throw line and scored a season-high ten points at Louisiana on January 28. Mannie posted a career-high five rebounds versus James Madison on February 9 and recorded a season-high four assists versus Oglethorpe on November 26, demonstrating his versatility and ability to contribute in multiple facets of the game.

2021-22

Mannie played in four games at Georgia Southern, making three of four field goal attempts, including one three-pointer, while totaling seven points and three rebounds.

High School

Mannie was ranked as a Top-200 player and the 16th-best combo guard nationally by 247 Sports, as well as one of the top-10 players in the state of Georgia by Hoopseen. Mannie was named to the McDonald's All-America nominee list and averaged 21.4 points and 4.8 rebounds per game as a senior at Mitchell County High School, earning first-team all-region honors and participating in the GACA North/South All-Star Game. As a junior, Mannie averaged 21.1 points, 5.3 rebounds, and 1.8 assists while leading Mitchell County to a 19-6 record and the A Sweet 16. Mannie was named first-team all-region, was an all-state nominee and McDonald's All-American nominee, and was selected to compete in the 2020 GACA North/South All-Star Game, establishing himself as one of Georgia's premier high school talents before continuing his career at the collegiate level.