Arsenal will speak to captain Pierre-Emerick Aubameyang after a video on Instagram showed the forward getting a tattoo.
Tattoo artist Alejandro Nicolas Bernal posted the social media clip on February 9 and in it the striker is seen to get a new tattoo on his hand.
It is unclear when the incident took place and if there has been a breach of coronavirus rules given Bernal could be part of Aubameyang's bubble.
An Arsenal spokesperson told the PA news agency: "We will speak to the player to remind him of his responsibilities and establish what has taken place."
Aubameyang scored a hat-trick for the Gunners in a 4-2 win against Leeds on Sunday in his first start for a month.
The 31-year-old was allowed to leave the Gunners' coronavirus-secure bubble in January to tend to his mother who was going through some health issues.