|Full name||Yuichiro Nagai|
|Date of birth||February 14, 1979|
|Place of birth||Shinjuku, Tokyo, Japan|
|Height||1.84 m (6 ft 1⁄2 in)|
|1998–1999||→Karlsruher SC (loan)||0||(0)|
|* Senior club appearances and goals counted for the domestic league only|
Nagai was born in Shinjuku, Tokyo on February 14, 1979. He joined J1 League club Urawa Reds in 1997. He was loaned out to German 2. Bundesliga side Karlsruher SC from 1998 to 1999. He played 21 league games and scored 4 goals for reserve team. In 2003, Nagai took over the number "9" jersey from iconic Masahiro Fukuda after the latter retired from the game. In 2006, Urawa won the champions in J1 League which is first J1 champions in the club history. In 2007, Urawa won first Asian title AFC Champions League. Urawa also won the 3rd place at 2007 Club World Cup. In 2009, he moved to Shimizu S-Pulse and played for the club in 3 seasons. After that, he played for Yokohama FC (2012–13), Arterivo Wakayama (2014) and Thespakusatsu Gunma (2015–17).
Nagai was a member of the Japan U-20 national team for the 1997 World Youth Championship. He played all 5 matches and scored 1 goal. He also represented U-20 Japan at the 1999 World Youth Championship. He played all 7 matches and scored a goal in the semifinal against Uruguay. Japan won the 2nd place. On April 16, 2003, he debuted for the Japan national team against South Korea and scored a goal in this match. He was also selected Japan for 2003 Confederations Cup. He played 4 games and scored 1 goals for Japan in 2003.
|Club statistics||League||Cup||League Cup||Continental||Total|
|Japan||League||Emperor's Cup||J.League Cup||Asia||Total|
|1997||Urawa Reds||J1 League||30||3||2||0||6||0||-||38||3|
|2009||Shimizu S-Pulse||J1 League||8||0||3||2||3||0||-||14||2|
|2012||Yokohama FC||J2 League||7||2||0||0||-||-||7||2|
|2014||Arterivo Wakayama||Regional Leagues||11||3||1||1||-||-||14||4|
|2015||Thespakusatsu Gunma||J2 League||31||0||1||0||-||-||32||0|
|Japan national team|