The new gymnasium was built over the basketball courts near the quadrangle. Construction of the gymnasium commenced in March 1978 and was officially opened in mid 1979.
Mazenod College won its first Eastern Independent Schools (EIS) Swimming Premiership. The coach of the winning team was Jim O’Doherty and the team manager was Fr John Sherman OMI.
The first Sportsmen’s Dinner held at Mazenod College was attended by over 150 students and their fathers. The idea for the event came from Mrs Hansen and members of the Open Football Team and included a three course meal with drinks waiters and special guests. The guests for the inaugural Dinner were Jack Reilly (goalie in the 1974 Australian World Cup Soccer Team), Wayne Richardson (VFL Collingwood Football Club Captain), Mick Henry (VFL Umpire) and Trevor Vincent (athlete).
The first Mazenod College House Athletics Carnival was held on the front oval. This also marked the first use of the college oval as a sporting fixture. Students participated as members of four houses – Albini (yellow), Charlebois (blue), Gerard (green) and Grandin (red). Events included 100, 220, 440, 880, Mile, Broad Jump, High Jump, Triple Jump, Shot Putt and House Relays. The House winners were Gerard over Grandin. Charlebois was third and Albini last. The whole event was organised and conducted by the college sports master, Fr McGillicuddy OMI.