Yellow and red cards have been a crucial part of football since the 1970 World Cup, but a white card was used for the first time last year.
Just over a year ago, football history was made by referee Catarina Campos in the women's game between Benfica and Sporting CP.
The pair of rivals met in the Portuguese women's Cup quarter-finals, with Benfica cruising to a resounding 5-0 win.
Advert
But the game went viral after what happened in the 44th minute, with Benfica 3-0 up.
A woman in the crowd complained of feeling unwell in the stands and so medical staff from both teams rushed quickly to her aid.
Campos proceeded to reach for her top pocket and brandished a white card, recognise the heroics of those involved.
The action was cheered and applauded by the record 15,000 fans in attendance at Benfica's Estadio da Luz.
The white card came about following an initiative of Portugal's National Plan for Ethics in Sport (PNED) to try and continue to practice sport with fair play.
It was encouraged by the Portuguese Football Federation (FPF) in tournaments but IFAB (International Football Association Board (IFAB) have not approved the use.
However, the football lawmakers have signed off on the introduction of new blue cards in what is the biggest refereeing change for decades.
The Telegraph say that the blue card is related to sin bins and will be trialled - despite UEFA president Aleksander Ceferin not being in favour.
A blue card will be issued in the event that a player commits a cynical foul to prevent a promising attack or displays dissent towards an official.
Top-tier competitions are expected to be excluded from the trials, though the FA Cup and Women’s FA Cup could feature in the testing next season.
Topics: Sporting CP, Benfica
Josh Lawless