Ledley's winner followed a free-kick by Ki Sung-Yueng, but Butcher felt Stuart Duff had been harshly penalised for a challenge on Emilio Izaguirre.

BBC: Joe Ledley heads Celtic's winner

The early fillip allowed South Korea to dictate the tempo of the first half, with full-backs Lee Young-pyo and Cha Doo-ri pushing forward at every opportunity, while British-based duo Park Ji-sung and Ki Sung-yueng dominated the experienced Greek pairing of Karagounis and Katsouranis in midfield.

BBC: South Korea 2-0 Greece

Ki Sung-yueng's free-kick from close to the right corner flag was inadvertently flicked on by Kostantinos Katsouranis at the near post into the path of onrushing centre-back Lee Jung-soo, who smartly adjusted his body position before volleying in from close range with goalkeeper Alexandros Tzoras nowhere in sight.

BBC: South Korea 2-0 Greece