Sports management firm Proactive has won permission to appeal over a £4.3m claim against Manchester United striker Wayne Rooney.
The firm failed in its bid to sue Rooney in July 2010 for what it claimed was unpaid commission on deals agreed when the player was at Everton.
It was ruled that a contract between Proactive and Rooney for him to pay 20% commission on deals was unenforceable.
Permission for Proactive to appeal was given at the High Court in London.
Judge Brendan Hegarty ruled in 2010 at Manchester Mercantile Court that the eight-year contract Rooney signed as a young Everton player was "an unreasonable restraint" of his trade, when the Football Association recommended a maximum of two years.
After that hearing Rooney said he was "delighted", and that the firm had tried to "exploit him" by demanding vast sums.
Giving permission for the appeal earlier, Lord Justice Ward said Proactive did have a prospect of success in its arguments over Rooney's contract.
He said: "The mere fact that this was a claim for millions of pounds is almost in itself a compelling reason to give permission to appeal."
Proactive's founder Paul Stretford, took Rooney with him in October 2008 when he left the firm, citing "huge and irreconcilable differences".