Køge BK Born in
Køge, Sjælland, before moving on to
Køge BK in the
Danish 1st Division, and represented Denmark at various youth levels. He made a good display in a pre-season friendly against many-times Danish champions
Brøndby IF, and was rumoured to be joining that club in April 2000. He signed a contract with Brøndby in May 2000, initially sending him on loan back at Køge.
Brøndby IF Ankergren eventually joined
Brøndby IF in the top-flight
Danish Superliga championship in January 2001. He made his debut in October 2001, and therefore played only one match as Brøndby won the
2001–02 Superliga title. Ankergren got his breakthrough with Brøndby following the retirement of club legend
Mogens Krogh in December 2002. He played all 15 Brøndby matches in the second half of the
2002–03 season, and helped the club win the 2003
Danish Cup. For the
2003–04 season, Brøndby bought goalkeeper
Karim Zaza who became their first choice, leaving Ankergren to spend the season as back-up keeper, playing only one match. At the start of the
2004–05 season, Zaza suffered an injury and Ankergren played the entire season as Brøndby's starting goalkeeper, even after Zaza had recovered. Ankergren finished the season setting a league record 18
clean sheets in 32 matches, and helped Brøndby win
the Double of both the 2004–05 Superliga and 2005 Danish Cup titles. Leeds signed goalkeeper
Frank Fielding as backup to Ankergren whilst Higgs was injured. The following matches for Leeds saw a slump in form with Leeds drawing against
Wycombe Wanderers and losing against
Exeter City and Carlisle United. Ankergren had a fine match for Leeds in the FA Cup match against
Tottenham Hotspur on 23 January 2010. He saved a first half penalty from
Jermain Defoe, and also pulled off a string of fine saves as Leeds earned a replay with a 2–2 draw. On 3 February 2010, Ankergren put in an impressive performance after making several impressive saves against Tottenham in the FA Cup despite Leeds losing 3–1. He was involved in a
penalty shoot-out for Leeds, but was unable to save a penalty for Leeds in the Football League Trophy Northern Area final second leg against Carlisle as Leeds were knocked out of the tournament after losing 6–5 in the shootout. After Leeds' number one goalkeeper Higgs returned from a long injury lay-off in a match against
Norwich City, Ankergren dropped back to the substitutes bench. Leeds were promoted to the Championship after finishing in second place. It was announced on 14 May 2010 that Ankergren would not be offered a new deal at Leeds and that he was free to find a new club. He was replaced at Leeds by a fellow Dane
Kasper Schmeichel who signed a deal two weeks after Ankergren was released.
Brighton & Hove Albion in 2015 On 6 August 2010, Ankergren signed for his former Leeds assistant manager
Gus Poyet at Brighton. He made his Brighton debut the following day, in Brighton's opening match of the season 2–1 win over
Swindon Town. He started well at Brighton, winning the
League One Player of the Month for September 2010. He won the award again in March 2011, keeping five clean sheets in eight matches. On 12 April 2011, he helped Brighton gain promotion to the Championship after a 4–3 win over Dagenham & Redbridge. ==Coaching career==