Arsenal's Premier League game against Aston Villa will be the first fixture to introduce concussion substitute trials.
Both teams will be given two concussion substitutes, on top of their usual three permitted changes, per match in the event of players being diagnosed, or suspected of suffering, a concussion.
Concussions have become a hot topic in football, with the debate reignited earlier this season after Arsenal's 2-1 defeat to Wolves in November.
Wolves striker Raul Jimenez was stretchered off after fracturing his skull, an injury he is yet to return from, and David Luiz continued until half-time before being replaced following the clash with the Mexican forward.
But following The International Football Association Board's [IFAB] push to trial concussion substitutes in the hope of them being permanently introduced to the Laws of the Game, the game at Villa Park will be the first to do so.
And former Premier League referee Dermott Gallagher outlined how a green and white card system will work.
"To keep it simple, this had to come as player safety is absolutely paramount. We only have to look back a couple of weeks to the David Luiz and Raul Jimenez incident," he told Sky Sports. "From Saturday, each team will have two concussion substitutes.
"The fourth official will go to both teams at the start of a game and he will give them three substitute cards in white and two green concussion substitute cards.
"If one team has to make a concussion substitute, they will hand a green card to the referee, and to balance that up, the opposing team will be given a white card so he can use an extra substitute.
"What is means, in essence, is that if for whatever reason one team has to use up two concussion substitutes, the opposing team will get two additional subs. That would mean them having five white cards, as well as two green cards should they need them.
"Theoretically, they could use seven substitutes in one game. We hope and pray that it never has to be used. Nobody wants to see that situation, but we do have a care and a duty of attention to players, and over the last couple of years we have seen some bad head injuries.
"If this does occur on Saturday or going forward, we now have that caveat. It's there to be used and it's a bit like insurance. You have to buy it, but you hope it never has to be used."
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