Sunderland have taped up the seats of fans who refuse to sit down during games.
Black Cats supporters who persistently stand throughout matches have been suspended from using their season tickets for games at the Stadium of Light.
A photo circulated on Twitter shows a seat with a note on it saying: "This season card has been suspended due to persistent standing."
The club have issued a warning on their website about people who break the law on standing during matches and insist they must act to protect the safety and the view of other fans.
They say they have received an "increasing number of complaints", particularly from fans in the South Stand, which say the game is being spoiled by others who stand throughout the 90 minutes.
The club said 38 fans have been ejected from the Stadium of Light so far, compared to just 20 last season.
Head of safety and security Paul Weir said: "We certainly don't wish to spoil the enjoyment of any supporters, we want a vibrant lively matchday atmosphere just as much as the fans do, but we also have legal obligations that we must be seen to be adhering to.
"We also have a duty of care to all of our supporters, including elderly and disabled fans who have contacted us very concerned that their enjoyment on a matchday is being compromised because people around them stand throughout the game.
"Naturally we want to ensure a safe, comfortable and enjoyable experience for everyone at the Stadium of Light and we'd ask supporters to listen to requests from stewards and help us to eradicate persistent standing for the sake of all fans."
There has been a mixed reaction on the Sunderland fans' Ready to Go online forum, with some welcoming the club's stance but others complaining the move will discourage a noisy atmosphere at the ground.