Robledo started his footballing career at
Huddersfield Town, playing as a
part-time amateur while he earned his money coal mining, though he never managed to break into the first team. He was able to give up the coal mining when he moved to
Second Division Barnsley during
World War II.
First Division club
Newcastle United signed him on 27 January 1949, for a fee of £26,500. The fee included his brother
Ted; this is because Newcastle were only interested in buying George but he refused to move without his brother. Robledo's league debut for Newcastle came in the 2–0 victory away to
Charlton Athletic on 5 February, while his first league goal came a month later in the
derby match against
Sunderland at
St James' Park. Newcastle came out of the match 2–1 winners, with Robledo's goal separating the sides, helping to quickly make him a fan favourite. The other Newcastle goal scorer was
Jackie Milburn, marking the start of one of the great striking partnerships in Newcastle United's history. Robledo went on to score 5 more goals in the last 12 games of the season. The following season, Robledo scored 11 goals for Newcastle, then netted 14 times in the
1950–51 season and became the first South American to play in the
FA Cup final, when Newcastle beat Blackpool 2–0 to lift the Cup. Robledo finished as
Division One's top scorer in the
1951–52 season with 33 goals, 39 in all competitions (equalling
Hughie Gallacher's record). Robledo finished the season by scoring the goal which defeated
Arsenal in the
FA Cup final, helping Newcastle lift the cup in successive seasons. The goal scored by Robledo was drawn by a young
John Lennon, who included it in the artwork of his album
Walls and Bridges in 1974. In the 1952–53 season, Robledo scored 18 times, taking his all time goals record for Newcastle to 91 and his league record to 82 (making him the highest scoring (non-Irish) overseas player in the English top flight, a record that was broken nearly half a century later by
Dwight Yorke). At the end of the season, Ted Robledo was sold to
Colo-Colo and George soon followed him, with Colo-Colo paying Newcastle £25,000 for his services. Both brothers were highly popular in Chile, and George ended as top scorer in the Chilean league in 1953 and 1954, with 26 and 25 goals respectively. On 23 November 1956, Robledo assumed as the President of the
Sindicato Profesional de Jugadores de Fútbol (Professional Trade Union of Football Players) in Chile. Robledo left Colo-Colo in 1958, and spent a year out of football, before signing for
Club Deportivo O'Higgins where he played out the final years of his career, until his retirement in 1960. ==International career==