George was a fast direct raiding left flanker with an eye for goal but unfortunately for the youngster first choice no.11, Jackie Hather, was an automatic selection and the flying Englishman was rarely injured and looked like he might go on to play forever! After six full seasons as an understudy, during which Mulhall played no more than 24 first team appearances, George finally got his chance when Hather was stood down. The winger's early performances made everyone sit up and take notice and his belated meteoric rise took on fairytale proportions when George was called up to play for Scotland in Belfast on October 3rd 1959.

Inside the space of two months George Mulhall had been transformed from a six year understudy into a Scottish International playing alongside the likes of Denis Law, ian St.John and Graham Leggat. In true fairytale style George capped a comfortable 4-0 Scottish win by scoring on his debut. With the Dons on a downward spiral Mulhall found it difficult to force himself back into the Scottish selectors plans but a transfer to Sunderland for £23,000 in September 1962 resulted in two more caps.

After seven seasons at Roker Park, George went to South Africa as a player coach with Cape Town City but returned to Britain in 1971 to take up coaching duties at Halifax Town. Throughout the 70s and 80s he was very much part of the managerial scene in the lower divisions of English football and enjoyed spells at Halifax, Bolton and Bradford City amongst others.