As Cristian Romero pulls on the famous red shirt, he hums the words to North London Forever before making his way into the tunnel at the Emirates Stadium.As the team walk out onto the pitch, Romero high-fives mascot Gunnersaurus, who points to the Argentinian’s brand new ‘Once a Gooner, always a Gooner’ tattoo on his right calf and gives a thumbs up.Unlikely? FantasyLand? Well, if Arsenal pursue their surprise interest in the 28-year-old centre-back, perhaps not.Not that Tottenham Hotspur appear willing to consider an approach from their neighbours and bitter rivals for their captain, let alone sanction a sale.He may have been born in Cordoba, northern Argentina, but after five years at the Tottenham Hotspur Stadium, the notion of Romero being allowed to head the four miles south to the Emirates feels extremely problematic at best, sacrilegious at worst.And yet, it wouldn’t even be the most controversial transfer in the history of the Arsenal-Spurs rivalry, let alone English football and certainly not globally. It would, though, add to the list of highly-disputed mooted moves that never happened.“I was asking myself why he’d choose Arsenal when you know how much it’s going to affect your personal life,” ex-Spurs defender Stephen Clemence previously told The Athletic. “That’s what surprised me most about his decision. You turn your whole life upside down with a move like that.”Sol Campbell was heading towards Tottenham-legend territory. Born a 30-minute drive from White Hart Lane in the Plaistow district of east London, academy graduate Campbell was still a teenager when he made his first-team debut for Spurs and would blossom into one of the Premier League’s best defenders, an England regular, their captain who lifted the League Cup in 1999 and a player who made more than 300 appearances for them.Then, aged 26, he left on a free transfer to further his career ambitions. Disappointing, yes, but understandable. Inter of Italy and Spain’s Barcelona were possible destinations, but instead Campbell shocked English football and caused unimaginable consternation and fury… by joining Arsenal.Spurs fans took this very, very well.They hung an effigy of Campbell from a lamppost on Tottenham High Road, flooded their stadium with ‘Judas’ banners when he returned as an Arsenal player, threw drink bottles and missiles in his direction and endlessly chanted ‘scum’, among many worse words. His new Arsenal team-mates had booed Campbell in training to prepare him for the reception but, well, nothing could quite compare to the abuse he took.Tottenham fans direct their anger at Sol Campbell in November 2001 (Tom Jenkins/Getty Images)“In hindsight, I’m not sure if I would sign him again, bearing in mind the difficulties he faced,” Arsenal’s then manager Arsene Wenger later said.It was the most controversial transfer in modern English football history, but one Campbell could justify via the two Premier League titles and three FA Cups he won in six seasons with Arsenal. “Spurs fans have not forgotten it, but it was the best thing I could have done for myself,” Campbell said.Fellow defender William Gallas may have gone in the opposite direction to Tottenham (also on a free) a few years later, but nothing has compared to Campbell’s move since.