Originally drafted by the Red Wings in the second round (60th overall) of the 2019 NHL Entry Draft, Johansson previously played for Farjestad's junior teams before making his professional debut with three games for the senior team in 2018-19. He also appeared in 40 games for Farjestad's under-20 club in his draft season, ranking second on the team and third among the league's defensemen with 29 points (5-24-29), alongside a plus-10 rating and 63 penalty minutes. The Karlstad, Sweden, native has totaled 38 points (9-29-38) and 79 penalty minutes at the under-20 level and 36 points (14-22-36) and 14 penalty minutes on the under-18 circuit. Internationally, Johansson owns two medals with Sweden, earning silver at the 2018 Hlinka Gretzky Cup and winning gold at the 2019 IIHF World Under-18 Championship. He is the son of former NHL defenseman Roger Johansson, who skated in 161 NHL games with Calgary (1989-93) and Chicago (1994-95).