The severity of the infringements is key and Fifa deems there to be different levels, with the most serious being a breach of article 19. It is unclear how many of the alleged Chelsea cases would fit into the higher end of the scale, although it is believed to be a significant number.

Chelsea would reject that, but one that would appear to do so is that involving Bertrand Traoré, a forward now at Lyon, who was signed to professional terms by Chelsea on 1 January 2014, the first available day after his 18th birthday. Pictures emerged of him playing for the club against Arsenal in a “non-competitive” game on 23 October 2011, when he was 16. The pictures came to Fifa’s attention in January 2016 and it is believed that they were the trigger for the investigation.