Early years Starting his career at the youth teams of
Hvidovre IF, he moved youth setup of multiple Danish champions
Brøndby IF. When he was no longer seen as a long-term prospect for the Brøndby goalkeeping position, he left Brøndby in the winter 1999, to rejoin Hvidovre. Andersen made his senior debut for
Hvidovre IF in the lower league
Danish 1st Division, and was recognized as a big talent.
AB In March 2002, Hvidovre owner, and professional goalkeeper,
Peter Schmeichel chose to end his engagement in the club. Hvidovre actively sought to off-load Andersen, one of two professional players in the squad. He was initially wanted by a number of clubs in
English football, including Schmeichel's club
Aston Villa and
Sunderland, the club of Danish international goalkeeper
Thomas Sørensen. Sunderland opted to buy
Norwegian international goalkeeper
Thomas Myhre instead, and no other foreign offers materialized. Andersen moved to
Akademisk Boldklub (AB) in the top-flight
Danish Superliga championship in August 2002.
Charlton Athletic He moved abroad to join English club
Charlton Athletic in a
DKK 8 million
transfer deal in June 2004. In his first season with the London club, he only made two first team appearances. Due to an injury sustained by first choice goalkeeper
Dean Kiely, Andersen started the
2005–06 season in the team. Charlton's poor mid-season form saw him dropped in favour of Kiely at first, then Thomas Myhre, who established himself as first choice as Charlton turned their season around. Andersen was reinstated into the lineup for the last two games of the season, when Myhre suffered an injury. In the 2006 summer
transfer window, Andersen looked ready to join
Leeds United on a season-long
loan deal, but as Charlton insisted on a clause to allow the club to recall Andersen at any time during the season, the transfer fell through at the last moment. In the first half of the
2006–07 season, he saw the loaned-in
Scott Carson become Charlton's starting goalkeeper.
Brøndby IF In November 2006, Andersen signed a transfer deal to move back to Denmark to play for Superliga side
Brøndby IF at the start of the January 2007
transfer window. and
Viborg FF, but was kept in the starting line-up and eventually upped his game. He helped Brøndby win the 2008
Danish Cup, and was named 2008
Danish Goalkeeper of the Year.
Later career In August 2011 he joined former teammate
Daniel Wass at
Évian in the French
Ligue 1 for a fee of DKK 2 million. In the summer of 2013 he signed a two-year contract with
Real Betis of the Spanish
La Liga. He was sent on loan to Dutch
Eredivisie side
Go Ahead Eagles on 30 January 2014 for the remainder of the 2013–14 season. On 19 May 2014, it was announced he would return to Denmark on a permanent deal, signing a three-year contract with
Superliga side
FC Copenhagen, the main rivals of his previous club Brøndby. On 17 June 2021, Copenhagen confirmed that he had left the club. On 12 September 2021, Andersen joined Danish amateur club
VB 1968. ==International career==