Nigeria international John Mikel Obi is appealing against a Norwegian court's decision not to consider his contract dispute with Lyn.
Obi claims his contract with Lyn is invalid
Helge Morten Svarva, Obi's lawyer, said his 18-year-client will appeal against a decision by the Oslo district court that such matters come under the jurisdiction of sports organizations rather than the judicial system.
Obi, who wants to join Chelsea, is claiming Lyn officials pressured him into signing a contract with Manchester United in April 2005.
His attorneys claim Obi's contract with Lyn was forged, rendering all other agreements invalid.
Svarva, who said they would be taking the matter to the Oslo appeals court, hopes they will overturn the district court's order that Mikel pay Lyn US$22,400 in legal costs.
"The ruling is wrong, in our opinion," Svarva told NRK, the Norwegian state radio network.
"There is also the question of costs for Mikel. We want to have it tested again."
No date was immediately set for the new hearing.
Obi left Norway in May 2005 but returned three months later, after Fifa ruled that his Lyn contract was valid.
But after suing Lyn in November, Obi left the club again in December and has not played club football since.