Arsenal forward Kai Havertz is among the players to have received a yellow card in this season’s Champions League.
In the Champions League, players will receive a one-match ban should they receive four yellow cards.
This rule runs from the start of the league phase until the end of the quarter-finals. After then, all yellow cards are wiped out and players cannot be suspended for multiple yellow cards.
The same rules apply for both the Europa League and the Conference League.
During the opening two rounds of Champions League, five players received two yellow cards, meaning they are entering this week’s third round of matches two cautions away from a one-match ban.
Players can also be suspended if they pick up six, eight or 10 yellow cards. This would also result in a one-match suspension every time a player hits an even number of yellow cards above four.
The five players currently on two yellow cards are: Armando Obispo (PSV Eindhoven), Hakan Calhanoglu (Inter Milan), Jan Virgili (Club Brugge), Marlon Gomes (Shakhtar Donetsk) and Serginio Dest (PSV Eindhoven).