Complex sentence: He joined AaB Aalborg after a public dispute with his former club Randers FC, which relegated him from being first choice in the summer transfer window of 2007, when buying Kevin Stuhr Ellegaard.
Split into simpler sentences: He joined AaB Aalborg in 2007, after a public dispute with his former club Randers FC. Randers relegated him from being first choice in the summer transfer window of 2007, when buying Kevin Stuhr Ellegaard.