The 28-year-old Dane, who joined Albion in June 2004, was a regular fixture in Tony Mowbray´s side as they won the Coca-Cola Championship title last season to secure a return to the Premier League.
Mowbray said: "The era of Bosman means the incentives offered by clubs to out-of-contract players are often decisive in whether a player stays or leaves. I´d like to thank Martin for his contribution last season and wish him all the best in his new challenge.
Copyright (c) PA Sport 2008, All Rights Reserved.
Do YOU want to write for GiveMeSport? Get started today by signing-up and submitting an article HERE: http://gms.to/writeforgms