Newly formed Southern League club Colchester United's manager Ted Davis had already unsuccessfully attempted to sign Pendergast from Bristol Rovers, but he eventually got his man on 9 December 1937.
[1][4] Pendergast made his Colchester United debut on 11 December 1937 in a 1–0 victory at Layer Road against Aldershot Reserves in the Southern League Mid-Week Section,[5] and scored his first goal on 1 January 1938 in a 6–1 home win against Barry.
[6] After scoring six goals in eleven outings, his Colchester United career came to an end against Bristol Rovers Reserves when he broke his leg on 5 March 1938.
Unwilling to risk re-signing the player due to his injury, the club released Pendergast at the end of the season.
During the outbreak of the war, Pendergast briefly returned to Colchester to play in some friendly matches arranged in the 1939–40 season during the autumn.