Mosman's first rugby team was formed in 1893 and played its first match wearing a variety of dark jumpers with single white stars stitched on the front. It did not become a club or compete in official competitions until the following year. The suburb's first rugby club was formed in 1894 as Mosman's Bay Junior Football Club and entered the Third Junior 'B' Division involving ten teams. The club's colours were officially listed as 'Navy with 4 inch Pink Band'. Mosman played its first match on 26 May 1894 against 'Union', a junior club from inner-Sydney, and finished its inaugural season in 7th place with four wins and five losses. One of Mosman's foundation players was Denis 'Dinny' Lutge who would become Mosman's only dual rugby international. After joining North Sydney in 1900 he played in Australia's inaugural Rugby Union test against New Zealand in August 1903 and three tests against the visitingGreat Britain side in 1904. In 1908 Lutge joined the switch to Rugby League and played against New Zealand in Australia's first official Rugby League series. When the first Kangaroos were selected to visit Great Britain in 1908-09, he was elected tour captain by the players. Sydney's sub-districts rugby gained its first major trophy in 1923, when W. H. Kentwell, then president of Mosman Rugby, presented the Kentwell Cup. Eight teams competed in that first Kentwell Cup, with Mosman the winner. It remains the trophy of Subbies First Division. In 1924, Mosman's Vice-President, James A. Burke, presented the Burke Cup for subdistricts second graders.
Recent developments
Since its foundation Mosman has competed at a high level in many different competitions and grades but has always valued a balance between playing success and mateship and camaraderie off the field. In 1989 the Club embarked on its most ambitious project, the refurbishment of its home ground facilities at Rawson Park. This required a huge effort on the part of the Committee of the day - dealing with Local Council and State and Federal Governments of different political persuasions proved interesting. Four years and $500,000 later, and with the help of Mosman Council and Telecom, the doors to the Clubhouse were opened on 26 September 1992. In 2019, Mosman fielded seven grade teams and 3 Colts teams in the NSW Suburban Rugby Union's 1st Division as well as 35 junior teams. Registrations in general represent over 200 grade players, 80 colts players and over 450 juniors drawn predominantly from the local area.
Premierships
Division One Club Championships: 1927, 1954, 1996, 2018, 2019
