Larsen was born in Korsør, West Zealand, Denmark, and from an early age joined the AGF academy of Hessel Gods Fodboldkostskole in tenth grade, where he was coached by the likes of Flemming Povlsen and Lars Lundkvist, and played for Grenaa IF's team in the Jutland Series and Denmark Series.
[1] He then left AGF and followed Lundkvist to Brabrand, where he played for two years in the second-tier Danish 1st Division, before signing with Silkeborg.
[4] His stay in Belgium was unsuccessful—after only 17 appearances and one goal, Larsen left the club due to recurring injuries.
[8] In his first season at the club, Larsen made 18 appearances for Midtjylland and scored three goals, as the team won their first Superliga title.
[10] On 11 October 2009, Larsen was called up for the Danish national team for a 2010 FIFA World Cup qualifier against Hungary, after Per Krøldrup was injured.