Peterborough boss Darren Ferguson has revealed they turned down three bids from Celtic for Lee Tomlin.
Celtic boss Neil Lennon admitted he was hoping to sign Tomlin before the transfer window shut in Scotland on Saturday.
However, Peterborough have resisted the overtures from the Scottish champions as they look to keep hold of the striker.
Celtic made their third bid for Tomlin, who was substituted at half-time of Peterborough's defeat to Crawley on Saturday, during the game and Ferguson feels it unsettled Tomlin.
"The third bid arrived during the game," said Ferguson. "If that's how Celtic want to do business that's up to them, but it didn't do Lee any favours.
"I'm not angry at Celtic, I'm just stating the facts and people can make their own minds up about what's gone on.
"The first bid they made was a waste of time anyway. They can't have watched him much over the past few years if that's all they think it's worth.
"He's not going anywhere anyway and he knows that. We have great experience of clubs bidding for our players and they never leave after one bid.
"Lee is a lad who loves playing football and I did think that when he got on to the pitch he would forget about the Celtic bids, but clearly that wasn't the case."
Chairman Darragh MacAnthony added on Twitter: "I used to be a Celtic fan. Not after today! What a day."