Mann played in 67 games during his second season in the NBA. The Florida State product averaged 7.0 points, 3.6 rebounds and 1.6 assists in 18.9 minutes per game. The 24-year-old shot 50.9 percent from the field, 41.8 percent from three and 83.0 percent from the free-throw line. The 2019 second-round pick started 10 games during the season, including six during the postseason, and averaged 11.6 points, 4.5 rebounds and 2.1 assists in 31.7 minutes per game. Mann scored double-digit points 25 times and 20-plus points four times, including a career-high 39 against the Jazz in Game 7 of the second round of the playoffs. During the career-high performance, the ex-Seminole went 15-for-21 from the field, 7-for-10 from three and 2-for-2 from the free-throw line. He also added two rebounds, two steals and one assist across 36 minutes during the 131-119 win. The 6-foot-5 guard grabbed five-plus rebounds 22 times and double-digit rebounds twice, including a season-high 12 during a 98-85 win over the Spurs on March 25. The second-year wing dished out multiple assists 33 times, including a season-high nine during a 126-109 win over the Rockets on April 9. Defensively, he registered multiple steals 10 times and multiple blocks four times. Per 36 minutes, Mann averaged 13.5 points, 6.9 rebounds and 3.0 assists.

Following four collegiate seasons at Florida State, Mann was selected by the Clippers with the 48th pick in the 2019 Draft. The 6-foot-5 shooting guard made his league debut during the second game of the season, a 19-point win over the Warriors on Oct. 24, posting one rebound. Mann scored his first points three games later, racking up four points, five assists, three rebounds and one steal in 10 minutes. On Nov. 16 in a win over the Hawks, the rookie had his first double-digit scoring effort (13 points) while also contributing eight assists and six rebounds. He swiped a season-high two steals during a win over the Grizzlies on Nov. 27 -- a mark he'd reach one more time during the season. About two months later on Jan. 22 against the Hawks, Mann blocked a season-high two shots. The rookie's best performance of the season occurred during the final game of the regular season, which was seeding play during the NBA bubble following the league's hiatus due to COVID-19. In that contest -- a win over the Thunder on Aug. 14 -- Mann produced season highs in points (25), rebounds (14) and assists (nine) while matching his season highs in steals (two). During the playoffs, Mann saw 27 minutes and totaled four points, seven rebounds, one assist and one steal. Overall, during the regular season, Mann averaged 2.4 points, 1.3 rebounds and 1.3 assists in 8.8 minutes.