Johnson's 1989 season was a standout, as he averaged 14.1 points, 3 rebounds, and 2.9 assists per game. His contributions were a bright spot for the Hawks, even as the team struggled to a 7-17 record. The following year, he continued his solid play, averaging 13.7 points, 2.4 rebounds, and 3.8 assists per game, helping the Hawks achieve a balanced 13/13 record and an eighth-place finish in the league.

The 1991 season was the peak of Johnson’s career with the Hawks. He averaged 14.5 points, 3 rebounds, and 4.8 assists per game, showcasing his all-around game. That year, he was part of the historic highest-scoring game in NBL history on July 27, 1991, when the Hawks lost to the Melbourne Tigers 186-158. In that game, Johnson contributed 15 points, 3 assists, and 2 steals.

Though Rod and his brother Terry Johnson never teamed up for the Hawks, they later played together with the Newcastle Falcons during the 1998/99 season, marking a special moment in their careers - coincidentally playing against the Hawks in the first ever game at then Wollongong Entertainment Centre, now WIN.

After leaving the Hawks, Johnson continued to build his legacy with other teams in the NBL. He joined the North Melbourne Giants in 1992, where he achieved the pinnacle of success by winning an NBL championship in 1994. He later played for the Canberra Cannons in 1998 and finished his NBL career with the Brisbane Bullets in the 1999/2000 season.

Following his retirement, Johnson returned to Wollongong, where he remained connected to the basketball community. He recently contributed as a coach in the Illawarra Junior Representative program, with his son coming through the ranks, continuing the Johnson family's basketball tradition.