William McGeough, who had boasted about being connected to the Glasgow underworld, was in Devon visiting his mother and went drinking with Mr Donnelly after missing his bus home to Scotland.
The violence started when Mr Donnelly borrowed McGeough's Blackberry phone to call a taxi. He went outside to get a better signal and McGeough followed him, accused him of 'mugging him off' and stabbed him ten times before battering him about the head.
McGeough, aged 42, of Grafton Place, Glasgow, was cleared of attempted murder but found guilty of causing grievous bodily harm with intent by a jury at Exeter Crown Court last month.
He was jailed for 15 years with a five-year extended sentence yesterday.