Ja-cheol Koo
MF · Born February 27, 1989
Age in each playoff game
- 2014 Group stage (June 17, 2014), South Korea vs Russia 1–1: 25 years, 110 days
- 2014 Group stage (June 22, 2014), South Korea vs Algeria 2–4: 25 years, 115 days
- 2014 Group stage (June 26, 2014), South Korea vs Belgium 0–1: 25 years, 119 days
- 2018 Group stage (June 18, 2018), South Korea vs Sweden 0–1: 29 years, 111 days
- 2018 Group stage (June 27, 2018), South Korea vs Germany 2–0: 29 years, 120 days
Age in each season
- 2014 (South Korea): 25 years, 105 days to 25 years, 136 days
- 2018 (South Korea): 29 years, 107 days to 29 years, 138 days