No matches were to be played until Peace was declared. Many Duffield players were in the Armed Forces. In 1916, soldiers from the Duffield Hospital were allowed to play on the courts.Duffield LTC was heavily involved with the formation of Derby & District Lawn Tennis Association. All future county matches were played at Duffield, which became 'The County Ground'.
In August 1914, war was declared. While members played on the first Saturday of the war, long trains laden with heavy guns moved slowly past the courts.