[2] He played in the Nike Elite Youth Basketball League (EYBL) following the season and averaged 17.6 points, 5.1 rebounds, and 6.5 assists per game.

[3] Collier suffered a meniscus injury in his knee while participating in workouts with the United States under-18 basketball team in May 2022, which caused him to miss the rest of the EYBL circuit.

[8] Collier won the 2023 Naismith Prep Player of the Year Award and was named Mr. Georgia Basketball.

[13][14] On November 16, 2022, Collier committed to playing college basketball for USC after considering offers from Cincinnati, Michigan, and UCLA.

[17] He started the Trojans' season opener against Kansas State and scored 18 points with three rebounds and six assists before fouling out of the game.