Career
During his time with Vålerenga, Hagen received the nickname "Panzer" from the club"s fans. Amongst other things he created a "hate list" of Norwegian football players in the club magazine Vål"enga Magasin, containing the likes of Vidar Riseth. The Kniksen award is the highest individual award for a Norwegian football player.
In December 2004 Hagen was sold to Zenit Saint St. Petersburg, becoming the first Norwegian football player to play in Russia.
In 2005 he played 28 league matches for Zenit, receiving 12 cautions. In January 2006 he was elected vice-captain by the team
On 31 January 2008 it was announced that Hagen would be joining Premier League club Wigan Athletic, signing on loan until the end of the English season.< However, he only made one appearance for the team, in the away defeat at Portsmouth. On 28 July 2008 Hagen appeared at the Vålerenga home game against Tromsø, where it was announced he had re-signed for the club until the end of the 2010 season.
The return of one of Vålerenga"s most popular players was well received with supporters.
During an interview in April 2014, Hagen admitted to bribing a referee in a European Match during his time with Zenit Street.Petersburg. Erik Hagen made his debut, aged 29 years old, for the Norwegian national team away to Scotland on 9 October 2004.