Allegations emerged last week that the FA were looking into a booking collected by an Arsenal player this season, and now it has emerged it is one of Granit Xhaka's cautions that is under the spotlight,
A spokesperson told The Yorkshire Post's sister paper, the Yorkshire Evening Post: "The FA is aware of the matter in question and is looking into it.”
Xhaka was booked for timewasting in the 86th minute of his side's 4-1 win, having earlier escaped further punishment for a foul on Raphinha.
It is said that a sum of over £50,000 was gambled on Xhaka being booked in the game.
The caution was Xhaka's second of the season in addition to his red card at Manchester City. He has since had two more yellow and one further red card, taking his career tally to 63 and five in 233 Arsenal appearances.