Ki Sung-Yong, born on 24th January 1989, is a professional footballer who plays for Korean Republic National Football team. He plays in the centre midfielder position.
Ki started his youth career while studying in the John Paul College in Australia in 2001. He played for the team that won the Under 15 Nationals for John Paul College in 2004. He went by the name David Ki in Australia.
Ki debuted his senior career in 2006 when he played for the FC Seoul team in 2006. He played with the team till 2009 and made 64 appearances and 7 goals for the team. In 2010 he started playing for the club Celtic FC, for which he still plays. He has given 10 appearances for the team so far.
He started playing at an international level in 2006 when he was selected for the Korea Republic Under 20 team. He made 14 appearances and achieved 1 goal for the team till the year 2008. In 2007 he became a part of the Korea Republic Under 23 team. In 2009 he was selected for the Korea Republic National football team.