Keegan said he resigned from his job as Newcastle manager last year after being asked to sanction the signing of Uruguayan Ignacio Gonzalez on the basis of grainy footage on an internet site.
"I resigned because I was being asked to sanction the signing of a player in order to "do a favour" for two South American agents," Keegan said in a statement issued by the League Managers Association.
"No one at the club had seen this player play and I was asked to sign him on the basis of some clips on YouTube. This is something that I was not prepared to be associated with in any way.
"The club knew that I objected strongly to this transfer and were aware that by continuing with it I was likely to feel that I had no option but to resign.
"Notwithstanding this they nevertheless went on to sign the player at very substantial cost to the club."
Gonzalez joined on loan from Valencia on transfer deadline day last year. He made two appearances for Newcastle but is now back with the La Liga side.
Keegan resigned on September 4, 2008, less than eight months after taking charge in his second managerial spell at the club, saying Newcastle had breached a term of his contract relating to player transfers - something denied by the club.
He said that on August 31 last year the club breached his contractual right to have the final say on transfers by signing Gonzalez "expressly against his wishes".
Keegan said that contrary to statements from the club at the time, owner Mike Ashley had not done everything possible to keep him at Newcastle. Ashley was subjected to a hate campaign by angry fans and tried to sell the club last year.
Newcastle were eventually relegated with former striker Alan Shearer in temporary charge of the team after Joe Kinnear, brought in by Ashley to replace Keegan, suffered ill health.
Keegan claimed that the club's actions had cost him around eight million pounds from the remainder of his contract and that damage to his reputation would mean the loss of 16 million pounds he would have expected to earn until his 65th birthday.
However, the two-week tribunal found in favour of the club which said a clause in Keegan's contract limited any compensation at two million pounds.
"We declare that Kevin Keegan was constructively dismissed by Newcastle United Football Club Ltd for which Newcastle United Football Club Ltd must pay to Kevin Keegan damages in the sum of two million plus interest to be assessed if not agreed," the tribunal said in a statement issued by the Premier League.
Newcastle denied Keegan's claim that he had the final say on player transfers, saying Director of Football Dennis Wise and Tony Jimenez were responsible for player recruitment.
However, in its report the tribunal said it had "no hesitation in accepting that the club's breach of contract in signing Gonzalez contrary to Mr Keegan's wishes amounted to a fundamental breach of his contract."
Keegan categorically denied that he had turned down an offer of four million pounds to settle the claim, saying that money was not the priority during the tribunal.
Thank you for reading 5 articles this month* Join now for unlimited access
Enjoy your first month for just £1 / $1 / €1
*Read 5 free articles per month without a subscription
Join now for unlimited access
Try first month for just £1 / $1 / €1
Get the best features, fun and footballing frolics straight to your inbox every week.
Thank you for signing up to Four Four Two. You will receive a verification email shortly.
There was a problem. Please refresh the page and try again.