|Full name||Masahiro Koga|
|Date of birth||September 8, 1978|
|Place of birth||Okawa, Fukuoka, Japan|
|Height||1.85 m (6 ft 1 in)|
|1994–1996||Higashi Fukuoka High School|
|1997–2006||Nagoya Grampus Eight||231||(15)|
|* Senior club appearances and goals counted for the domestic league only|
Koga was born in Okawa on September 8, 1978. After graduating from high school, he joined Nagoya Grampus Eight in 1997. He became a regular player as center back from 1998. The club won the champions 1999 Emperor's Cup. He moved to Kashiwa Reysol in 2007. Although he played as regular player, he lost his opportunity to play for injury in 2010. So, he moved to Júbilo Iwata in August 2010. After playing in 2 seasons, he moved to his local club Avispa Fukuoka in 2012. He retired end of 2015 season.
National team careerEdit
In August 1995, Koga was selected Japan U-17 national team for 1995 U-17 World Championship and he played full time in all 3 matches. In June 1997, he was also selected Japan U-20 national team for 1997 World Youth Championship, but he did not play in the match.
|Club performance||League||Cup||League Cup||Total|
|Japan||League||Emperor's Cup||J.League Cup||Total|
|1997||Nagoya Grampus Eight||J1 League||8||0||1||0||5||0||14||0|
|2007||Kashiwa Reysol||J1 League||29||2||1||0||2||1||32||3|
|2010||Júbilo Iwata||J1 League||12||0||2||0||3||0||17||0|
|2012||Avispa Fukuoka||J2 League||33||1||2||0||-||-||35||1|