Old Collegians first played in 1937 as Prince Alfred Old Collegians Rugby Club. During World War II, the competition ceased from 1941 and the club was reformed on the renewal of the competition in the state in 1945. The club was then named Old Collegians Rugby Club. OC's first home ground was in the centre of Victoria Park racecourse; the club later moved to the dairy cow-grazed pastures of the south parklands and in 1953 moved again to its current location at Tregenza Oval. In the early 1980s the club ran an U/18 team for three years and then formed the Junior Collegians in 1985. OC now competes in each junior age bracket. OC is one of the two founding clubs of the women's South Australian rugby competition and the only club to compete continuously from the first games in 1995 until 2018. Many OC players have captained or represented the state at senior and junior levels over the years and have taken out SARU individual player awards. The greatest achievement so far has gone to Rod Hauser, who was selected for the Wallabies while playing for OC. In 2013 D'arcy Sadler was contracted to the Australian women's sevens squad while continuing to play for OC between tournaments. The Club Guernsey has changed colours from the initial maroon and blue jumper with a PAC crest, to broad maroon and navy hoops in 1955, to its current light red and blue hoops in the mid 1970s. The club's 75th year in 2012 was celebrated with a gala dinner attended by over 550 people.
Controversy
Despite a history of 24 years at the club and winning the state women's premiership in 2018, the vast majority of the women's team left the club when their complaints of bullying, mistreatment and misogyny were not responded to by the club. The women’s team raised concerns about their alleged unequal treatment at the club, which were not adequately addressed. Subsequently, approximately 20 players transferred to Adelaide University to go on and win the 2019 premiership there. Among other concerns, at Old Collegians the 2018 women's team had not been allowed to climb the club rafters to celebrate their win. The tradition had been, winning premiership players were allowed to climb into the clubroom rafters on the Grand Final evening to celebrate their win. Due to safety concerns, this practice was officially banned by the committee prior to the 2016 premiership teams repeating the practice without apparent recourse or penalty. A sexual harassment complaint was also made to the club about the treatment of one female player by a male coach. Even though the club was unable to fielded a women's team in 2019, they were awarded a $500,000 Federal taxpayer-funded grant the following year, for "construction of female change rooms and facilities" as part of the 2020 "sports rorts" controversy. The club asserted it to be a proper use of funds on the basis that the club had a women’s team continuously for the 24 years prior to, and at the time of application, and their junior membership contained a significant number of girls. If the merit based process of application assessment conducted by Sport Australia had been followed, the cut-off score would have been 74 out of a possible 100. Old Collegians’ application had been given a score of 60.5. Beyond making the application, the club had no influence over the approval of the Federal grant.