Simon Grayson says Darron Gibson has admitted to being "bang out of order" over his comments about fellow players not trying hard enough – but says he will personally drive anyone not committed to Sunderland to new clubs.
Gibson was filmed in a bar on Saturday night criticising colleagues in the aftermath of the 5-0 home friendly defeat to Celtic.
"I think it's been acknowledged that it wasn't a very good thing to do," Grayson told BBC 5 Live. "The club have dealt with it internally.
"We've decided on the plan of action and that's deal with it internally.
"Players should be more responsible in this day and age.
"Social media plays a massive part in football, people are there to wind people up and make you say things you shouldn't say.
"Darron Gibson has admitted it and apologised that he was bang out of order, it has been dealt with.
"It is something that we didn't need leading up to the start of the season.
"Unfortunately, it happened and we dealt with it and we can look forward to the start of the season now."
The likes of Lamine Kone, Wahbi Khazri and Jeremanin Lens were mentioned by fans to Gibson, and the trio are all expected to leave the Stadium of Light before the transfer window closes.
And Grayson says that he only wants players at the club who are committed to the cause, otherwise he’ll drive them to wherever they want to go himself.
"I need to call on all the players who are at my disposal," said the 47-year-old.
"There are players who will leave in the next few days and weeks while the window is still open and new ones will come in.
"The ones we bring in are going to have to be the right types, with hunger and desire.
"I've said to the players that if anyone doesn't want to be at the football club my door is open and I'll drive you to wherever you want to go to.
"I want players who want to play for this football club."