A relationship where the fierce competition among players and supporters has, at various times, extended to the boardroom in the 18 years since Roman Abramovich took over at Chelsea. They, along with many others, have attempted to explain to The Athletic the nature of the off-field relationship between two of England’s most powerful clubs. The north London derby is a footballing rivalry Chelsea-Spurs has been football plus boardroom.” A source who deals with both is discussing the relationship between the two London clubs before Sunday’s derby. Put them together, and there have been times over the last decade or so when it’s been as competitive in the boardroom as it’s been on the pitch. (Additional contributors: Dominic Fifield, Simon Johnson) “ Chelsea and Tottenham are both extremely tough negotiators - they go into battle and they fight.