It involved Eddie Baily, the brilliant inside forward in Spurs' first league title triumph. Baily was on Spurs' books as an amateur in 1939, but the Second World War happened and the exciting youngster was sent to Belgium, the Netherlands and Germany with the Royal Scots Fusiliers.
However, rumours that Baily was killed in action made their way back to north London and his registration was allowed to lapse, so when he returned to Britain he found himself without a club and this is when he signed for Chelsea.
Spurs' historian, John Fennelly, explained the error was only spotted when Baily dropped by White Hart Lane to collect his kit, but once the mix up was explained to Chelsea, they released him from his contract and in February 1946 he was a Tottenham player again.
"In a team of class performers, Baily was the true star," Fennelly told tottenhamhotspur.com.
But he was more than just one of Spurs' best players. His flair and intelligent play saw him stand out among his peers and you'll find almost every reference to him claim he was one of the best inside forwards of his generation; a vital part of the 1951 title winners, who made the 'push and run' style famous under Arthur Rowe.
He made his Tottenham debut in January 1947 and by 1950 he was a Division Two champion, with the club winning their first top flight crown a year later.
Bill Nicholson was his team-mate in that side and he later brought Baily in as his assistant in 1963 where it wasn't uncommon to hear him use wartime metaphors in his pep talks - 'right, bayonets on' or 'over the top'.
He left with his manager in 1974, having won two League Cups, the FA Cup and UEFA Cup with the club on top of his playing honours. He later became West Ham's chief scout and retired from football in 1992.
Baily's status as a Tottenham icon was established long before his death in 2010 at the age of 85 – and to think the club owe such huge thanks to a team that became such huge rivals.