Sunderland manager David Moyes admits he is not impressed with the actions of defender Patrick van Aanholt after pictures of the Dutchman smoking surfaced on social media.
The former Chelsea left-back had to be withdrawn from last week's fixture against Tottenham after a cardiologist recommended the Black Cats rest the player due to a heart problem.
However, The Sun leaked images this week of the 26-year-old smoking a hookah pipe which went viral on social media.
"I don't expect a player to do that, I don't expect a player playing for me doing that. I have a had a word with him. I am not impressed," Moyes told reporters.
"I also have to say, it was a picture from six weeks ago, it was in his own time, not during the season, but let me make clear I don't condone it at all.
"It is a bad thing for us to show our younger children, and for supporters to see players [doing that] I don't think it is a good thing at all.
"They are role models to so many kids, they are watched all over the world. Things are done with Twitter and all the other things now, you have to be careful and aware of how you behave."