Not many transfers occur between Tottenham and Arsenal, but when they do, they cause an uproar of epic magnitudes.
The biggest of them all was the decision by Sol Campbell in 2001, whose contract was running out at White Hart Lane, to leave Spurs and join their North London neighbours on a free transfer. To this day the centre-back has never been, and never will be forgiven.
If it was thought that the Campbell transfer, and the aftermath of it, would never be matched again, well if Alderweireld decides to make the unlikely move to the Emirates Stadium then expect bigger shockwaves.
There is no doubt that it would cause a bigger uproar on one side of North London, and just like Campbell, he would go down as a 'Judas' forever.
But given Arsenal's recent problems, the pure unlikelihood of it happening and Tottenham's current position, a switch across the road would no doubt be the biggest shock of the 21st century.
Spurs are a different kettle of fish now and they are even competing at a higher level than their bitter rivals, who are in the Europa League, whilst their neighbours are one game away from the Champions League semi-final.
Either way, with all the speculation surrounding Alderweireld's career, it won't be a surprise to see him stay put and help Mauricio Pochettino lift his first trophy at the club – that's if he doesn't do it this season.