Japanese footballer
 is a Japanese former professional footballer who played as a defender.
Club career.
Tsuboi was educated at and played for Yokkaichi Chuo Kogyo High School and Fukuoka University.
After graduating from the university in 2002, he joined Urawa Red Diamonds and immediately broke into the first team. His first appearance came on 3 March 2002 against Yokohama F. Marinos in opening game in 2002 season. He scored his first league goal on 17 May 2003 against Gamba Osaka. He won the Rookie of the Year award in 2002 and was selected as one of the J.League Best Eleven in 2003. In 2006, Reds won the champions in J1 League which is first J1 champions in the club history. In 2007, Reds won first Asian title AFC Champions League. Although he played many matches as regular center back until 2010, he could not play many matches from 2011.
In 2015, Tsuboi moved to Shonan Bellmare. However he could not play many matches and Bellmare was relegated to J2 League end of 2016 season. In 2018, he moved to J2 club Renofa Yamaguchi FC.
International career.
Tsuboi represented Japan for the 2001 Summer Universiade held in Beijing where the team won the title beating Ukraine in the final.
Japan's national coach Zico gave him the first cap in 2003 when he played Tsuboi on 11 June 2003 in a friendly against Paraguay at Saitama Stadium. He was a member of the Japan team for 2006 FIFA World Cup where he played 2 games against Australia and Brazil. In Japan's first match against Australia, he suffered from cramps in his both thighs and had to be replaced by Teruyuki Moniwa in the 56th minute.
He was also in the squad for 2007 Asian Cup but did not play any game in the tournament as Yuki Abe and Yuji Nakazawa were the first-choice centre backs.
On 8 February 2008, he announced retirement from international football. He played 40 games for Japan until 2007.
Honours.
Urawa Reds
Shonan Bellmare
Individual
References.
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