While in eighth grade, Springer played varsity basketball for Lighthouse Christian School in Antioch, Tennessee, averaging a team-high 19 points and 3.5 rebounds per game.

[3] As a sophomore, he averaged 24.7 points, 10.2 rebounds, 2.4 steals and 2.4 blocks per game, helping Rocky River reach the Class 4A state semifinals.

[12] Springer began receiving scholarship offers from NCAA Division I basketball programs during his freshman season in high school.

[17] As a freshman, Springer averaged 12.5 points, 3.5 rebounds and 2.9 assists per game, earning Southeastern Conference (SEC) All-Freshman Team honors.

In his sophomore season, Springer won the NBA G League title with the Blue Coats and was named the championship game most valuable player.

Springer had an impressive performance in the 2024 NBA Summer League, showcasing his skills and potential to secure a more significant role with the Boston Celtics.

In the Celtics' first game against the Miami Heat, Springer led the team with 23 points, demonstrating his scoring ability and potential to play lockdown defense.

[25] On January 22, 2025, Springer scored 8 points and had 4 steals (tying his career high) in a 117–113 overtime win against the Los Angeles Clippers.