Mario Been moved to NEC Nijmegen in succession of NEC favorite Ron de Groot.
Ron de Groot resumed his original position as an assistant-coach.
Mario Been came with the image to return the glory years back to the club.
In his first season 2006–07 he led the club to a tenth-place finish in the Eredivisie.
With the signing of a few players during the summer of 2007 he molded a competitive and attractive team.
However, the first half of the 2007–08 season did not go well for Mario Been as his side were sitting bottom of the league at the start of the new year.
However, Been managed to remarkably change the fortunes of his team as they went on a run which saw them eventually end 8th in the league standings.
This earned the club a UEFA Cup Play-off berth against three other Dutch teams.
Been got his team to play very attractive football which resulted in plenty of goals.
In the final play-off round against NAC Breda his side won 6–0 at home, and 1–0 away.
For the first time Mario Been had qualified a team for European competition.

The season of 2008–09 would be the finest season to date for Mario Been as professional manager.
His side were drawn in a tough group in the UEFA Cup with away games at Spartak Moscow and Dinamo Zagreb, while Tottenham Hotspur and Udinese Calcio would come to Nijmegen.
At the start of the European campaign his side were labeled the whipping boys of the group.
However, after two losses in the group (3–2 against Dinamo Zagreb and 1–0 against Tottenham Hotspur), NEC managed to beat Spartak Moscow in Russia with a scoreline of 2–1.
Lasse Schöne scoring the all important goal in that match.
The final and decisive game for Been would against Udinese, on a wonderful night for the club, he managed to get the team to a 2–0 scoreline and secure progression to the next round.
They eventually lost 4–0 on aggregate to Hamburger SV in the following round, but Mario Been had already written himself into the club's history.
 On 28 January 2009, NEC Nijmegen and Feyenoord had reached an agreement to let Been move to Rotterdam to become the head coach and manager there for the next season.
On his final match as manager for NEC Nijmegen, Been was applauded by a full Goffert Stadium, with fans singing his name and the players, board and fans giving him the honour of being one of the best managers the club has ever had.
Been's farewell speech was filled with tears, however, his last words to the fans epitomized his legendary status at the club.
Mario Been moved to NEC Nijmegen in succession of NEC favorite Ron de Groot. Ron de Groot resumed his original position as an assistant-coach. Mario Been came with the image to return the glory years back to the club. In his first season 2006–07 he led the club to a tenth-place finish in the Eredivisie. With the signing of a few players during the summer of 2007 he molded a competitive and attractive team. However, the first half of the 2007–08 season did not go well for Mario Been as his side were sitting bottom of the league at the start of the new year. However, Been managed to remarkably change the fortunes of his team as they went on a run which saw them eventually end 8th in the league standings. This earned the club a UEFA Cup Play-off berth against three other Dutch teams. Been got his team to play very attractive football which resulted in plenty of goals. In the final play-off round against NAC Breda his side won 6–0 at home, and 1–0 away. For the first time Mario Been had qualified a team for European competition.
The season of 2008–09 would be the finest season to date for Mario Been as professional manager. His side were drawn in a tough group in the UEFA Cup with away games at Spartak Moscow and Dinamo Zagreb, while Tottenham Hotspur and Udinese Calcio would come to Nijmegen. At the start of the European campaign his side were labeled the whipping boys of the group. However, after two losses in the group (3–2 against Dinamo Zagreb and 1–0 against Tottenham Hotspur), NEC managed to beat Spartak Moscow in Russia with a scoreline of 2–1. Lasse Schöne scoring the all important goal in that match. The final and decisive game for Been would against Udinese, on a wonderful night for the club, he managed to get the team to a 2–0 scoreline and secure progression to the next round. They eventually lost 4–0 on aggregate to Hamburger SV in the following round, but Mario Been had already written himself into the club's history.  On 28 January 2009, NEC Nijmegen and Feyenoord had reached an agreement to let Been move to Rotterdam to become the head coach and manager there for the next season. On his final match as manager for NEC Nijmegen, Been was applauded by a full Goffert Stadium, with fans singing his name and the players, board and fans giving him the honour of being one of the best managers the club has ever had. Been's farewell speech was filled with tears, however, his last words to the fans epitomized his legendary status at the club.
Mario Been