Victorian State champion 1907, 1908, 1912, 1913, 1915, 1916, 1917, 1918, 1919, 1920 and 1922.

Gundersen also competed in the 1914 Mannheim candidate masters event, scoring 2.5/11 before the outbreak of World War 1 stopped the tournament.

Sources:
Anthony Wright "Australian Chess to 1914", Melbourne 1995 John van Manen "The Records of Australian Chess - Tournament and Match Tables - Volumes I & II", Modbury Heights, 1987

The outbreak of the first world war found Gundersen in Germany, where he was competing in the Hauptturnier at the Mannheim congress. Many of those present who were not Germans or Austrians were arrested, including Alekhine, who later escaped and returned home to join the Russian army. Others, including Rubinstein and Bogoljubov, were interned for the duration. Gundersen himself got out through Denmark, using a false passport, which he later had framed.

The club's records say little of the great war. Tournaments were organised for the Red Cross and the Wounded Soldiers fund. There has not come down to us the Honour Roll that hung in the clubroom of members and their sons who had enlisted. Gundersen wrote the Australasian's column from 1910 to 1938, when he retired from active play. His chess library was extensive and his authority as a chess historian was unquestionable.

(There is in the Anderson collection a copy of Walker's Chess Studies, from Gundersen's library. Published in 1844, it was bought by Sir George Stephen, and came to Gundersen via Louis Goldsmith. The book contains some games played by Stephen in 1850, one with notes by Staunton.)

Gundersen and his wife were much given to entertaining visiting players at their home "Tristan" in Mathoura Rd, Toorak, where dinner was followed by Kriegspiel, cricket and song. <Cecil Purdy once described Gundersen as the soul of the club.>"

<The death occurred yesterday of Mr Gunnar Gundersen, BSc, of 88 Mathoura rd, Toorak. Mr Gundersen's father was Scandinavian Consul for some years before appointment of separate Consuls for Norway and Sweden. A Wyselaskie scholarship winner, Mr Gundersen in 1920 was appointed to the staff of Melbourne University, and from 1923 was senior lecturer in mathematics until 1942, when ill-health compelled him to relinquish the post. In this period he also acted as professor in Professor Mitchell's absence abroad. For many years Mr Gundersen edited the weekly chess column in The Australasian. He was a life member of Melbourne Chess Club, and was 12 times holder of the Victorian chess championship title. He leaves a widow (who is a sister of John Amadio, flautist) and one son. His sister, Dr Sara Gundersen, is senior lecturer in bacteriology at Mellbourne University. The funeral will leave A. A. Sleight's chapel at 3.30 tomorrow for Springvale Crematorium.>