Norwich City have revealed Dean Ashton waived £150,000 of money the club owed him to move to West Ham for £7.25m.
Dean Ashton cost West Ham £7.25m from Norwich
City chief executive Neil Doncaster said the move would have been off had the 22-year-old striker not written off bonuses owed by the Canaries.
Doncaster said: "We made it clear we needed more money to make the move happen and West Ham refused to pay a penny more.
"Dean waived around £150,000 of money we owed him to make it happen."
Ashton was owed £400,000 from the deal under the terms of the contract he signed when he moved to Carrow Road a year ago.
But, he waived £30,000 of that money and also other bonuses to make the Upton Park move happen.
Other money included all bonuses for December, his January salary and bonuses and the whole of his outstanding signing-on fee.
Doncaster said: "This was a crucial part of the ambitious step of bringing him here in the first place and re-negotiating his deal in the summer.
"Without it, we may have not got the player in the first place or have lost him for far less money than we eventually received
Norwich also had to pay Crewe £350,000 outstanding from the original £3m transfer fee and £800,000 from the £4m profit as part of their 20% sell-on clause.
The former England Under-21 international scored 18 goals in 45 games for the Canaries.