Niall Quinn has warned of agents who scupper transfer window deals by misrepresenting players.
The former Sunderland chairman told The Footballers' Football Show that the January window is a minefield worsened by the presence of agents muscling in on deals.
And he says that during his days in the Stadium of Light boardroom between 2006 and 2011, he would often be involved in last-minute negotiations with agents he'd never met before.
"You're in a trench situation until you get to Deadline Day," said Quinn who appeared on the show with former player John Carew and agent John Mac.
"There's a load of guys out there telling [players] 'I've got four other clubs for you'. Building the ante up, getting more money from the club.
"Someone arrives at the 12th hour and you've never met him in your life, and he's saying 'this deal doesn't go through unless I'm on the paperwork'. And that happens!"
New Year nightmares
The transfer deadline irks Quinn and he said his relationship with former Sunderland boss Steve Bruce would often become strained during the window.
He said he fell out with him over the purchase of Anton Ferdinand in 2011 and predicts similar scenes at football clubs around the country over the next few days.
"This ridiculous cap at the end that says you can't go past that date... naturally all the business starts to gravitate towards that and the strengths and weakness on the weight of that point are found out.
"You can't come on the 2nd or 3rd January and say 'I'll give you everything you want' because you'll just get brought on to the end anyway.
"The thing to do is offer very little at the start of January, the newspapers get hold of it, somehow - magically. The speculation starts and it's game on.
"You end up falling out with your own manager - I can remember Steve Bruce and I at loggerheads time and time again. We'd have issues and I wouldn't be doing my job properly if we didn't.
"We had players parked nearby, ready to come, but I was the one holding back because we hadn't got the sale through that we thought we were getting earlier in the day.
"It was Anton Ferdinand at Queens Park Rangers and it went through very late. That four of five hours Steve Bruce and I probably fell out the most. It is absolutely horrific."
Asamoah Gyan, who Quinn signed for Sunderland 2010, was eventually sold to Emirati club Al Ain in 2012 due to problems with his agent.
The club had not intended to sell their striker, but behind-the-scenes difficulties forced them to offload him.
"He went down to Wembley to play for Ghana against England and he scored in a 1-1 draw," Quinn recalled.
"Everything was great and he came back up and he'd had a problem. His agent - who we knew and we'd worked with - was upset.
"After the game [Gyan] had signed with a new agency and came back to us and asked us to get him out of it. These are the kind of things that footballers do."