A third card has been used in football alongside the traditional red and yellow cards.
It had originally been suggested by former UEFA president Michel Platini to represent the sin bin.
Unlike the two cards fans are familiar with the white card isn't a punishment
Football fans will be very familiar with the sight of red and yellow cards that have been a staple of the game since the 1970 World Cup in Mexico.
But what may be a more unfamiliar sight to those who regularly watch the sport is that of a white card.
Initially used in a women's cup clash between Sporting Lisbon and Benfica it's second use was also in Portugal but this time in the fifth division.
And while the two cards most seen are used by referees to punish players, this new third card is used for something quite different.
Mail Sport breaks down everything you need to know about the white card.
The White card is used to mark an act of sportsmanship by a player.
What is a white card and when is it used?
The card can be shown to recognize and encourage fair play and is designed to 'improve ethical value in the sport'.
The move is part of a new initiative in Portugal to encourage sides to act in a sporting manner and receive instant recognition for their positive actions.
The white card provides immediate recognition for a positive act during a football match.
The initiative isn't widespread just yet and is currently consigned to Portugal, but it's part of a wider series of new introductions in football.
The referee brandished it as a recognition of their sportsmanlike conduct during the match
Hasn't this been mentioned before?
Technically, yes. Previously, former UEFA president Michel Platini had called for the introduction of a white card as a punishment for dissent, that would leave guilty players in a 10-minute sin-bin.
Michel Platini had previously suggested the introduction of a white card - but for different reasons.
Platini suggested the white card to help combat the 'craze of contesting the referee', which he branded 'a veritable epidemic in football'.
The Frenchman's ideas went no further, though.
Could we see it in the Premier League?
It is unlikely that we will see the card brought into the Premier League anytime soon.
For the time being, it remains a Portuguese initiative only - rather than anything led by the International Football Association Board - so eyes will be kept on how it is received in the coming months.
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