As an amateur union player he represented Kenfig Hill, Treorchy and Glamorgan Police RFC, while as a professional rugby league footballer he played for Hunslet, Leeds and Dewsbury.
After leaving school he joined local club Kenfig Hill, but by the time he was selected to represent Wales in 1926, he had switched to Rhondda team, Treorchy.
His first international appearance was in the opening Wales game of the 1926 Five Nations Championship; played against England at the Cardiff Arms Park.
David Morgan Jenkins played at prop in Glamorgan's 18-14 victory over Monmouthshire in the non-County Championship match during the 1926–27 season at Taff Vale Park, Pontypridd on Saturday 30 April 1927.
[5] David Morgan Jenkins played at prop, and scored a try in the Hunslet FC's 7-13 defeat by Hull Kingston Rovers in the 1929–30 Yorkshire Cup Final during the 1929–30 season at Headingley, Leeds on Saturday 30 November 1929, in front of a crowd of 11,000.