It can feel as though football's governing body FIFA make the rules up as they go along.
In 2017, Leicester City were denied the chance to sign Adrien Silva from Sporting CP because they missed the deadline by 14 seconds. Yet, Andrey Arshavin officially signed for Arsenal four days after the winter window closed in 2009 due to various layers of bureaucratic wrangling.
While the deadline on deadline day is not always clear cut, the Premier League rarely fails to live up to its reputation as football's ultimate soap opera, saving most of the drama for the final moments of the window.
Here are some of the most dramatic, bizarre and confusing moves to have taken place at the turn of the year.
Fulham won the race to sign the highly rated Collins John in the winter of 2004, outmanoeuvring pre-takeover Manchester City as manager Chris Coleman and amiable goalkeeper Edwin van der Sar led the charm offensive.
That the cottagers snagged the 18-year-old striker was impressive enough but his presentation is even more eye-catching.
John Collins, Fulham's recently retired Scottish midfielder, happened to be at the stadium when the club's deadline day arrival was announced and a lightbulb went off in the head of one enterprising soul. John Collins would accompany Collins John onto the pitch.
«I met him in the tunnel and thought people were taking the Michael,» Collins recalled. Fulham's new striker got the joke.
«I had heard the name John Collins of course because I have studied football,» John reflected. «They introduced him and then me and I thought that was very funny.»
Lionel Scaloni's manager at Deportivo La Coruna, Joaquin Caparros, didn't have a place in his starting XI for the right-back but espoused a word warning that was
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