The 23-year-old forward turned some heads with his performances for Sheffield United, where he scored 14 goals while assisting eleven to take the Blades back to the Premier League.
Ndiaye was keen on a move to Marseille this summer and the Blades accepted a €17m offer to let the forward join the French outfit.
Bettis insisted that they tried to keep Ndiaye at the club by offering him an extension, but the Senegalese international and his agent rejected their offer to have more control over the future.
The Blades chief executive officer believes that the club cannot be blamed for selling Ndiaye, as the player and his agent wanted control over the whole transfer scenario to get his desired move.
“Iliman was offered a contract the season before and during the season, all of which he turned down”, Bettis was quoted as saying by Yorkshire Live.
“There was a desire from the player and agent to have control over the next step and I understand that.
“They felt there was a next step for Iliman which was away from this football club because they believed, as we all do, that he has the ability to go on and be bigger and better and needed a different stage to do that.
“They were very clever about the way they managed it and the blame can’t always just be put at the club’s door.
“Equally, we can’t just be writing cheques for any amount that any player wants to stay because there wouldn’t be a club here.
“We’d be broke.”
Paul Heckingbottom’s side managed to bring in a host of new faces to Bramall Lane to strengthen their squad with a cash boost from the sale of Ndiaye.
