The crowd for Swansea City's Coca-Cola League One opener against Tranmere could be slashed if the club's pre-season friendlies do not pass without a hitch.
The club welcome Fulham to The New Stadium Swansea today.
Director David Morgan has admitted problems at the game could mean a reduced capacity for Tranmere's visit on August 6.
"The safety advisory group (SAG), which is made up of representatives of Swansea Council and the emergency services, will be watching to see how things go at the Fulham game," he said.
"Ideally, the capacity will go from 12,400 today to 20,500 for Tranmere.
"But the SAG committee will be looking at how well the fans adapt to the new stadium.
"A large number of our fans are used to standing up throughout games and smoking. At the New Stadium, neither of those things can happen.
"Other things will be monitored - the way the crowd arrive, the way they leave and the state of the roads around the stadium.
"Everything is being watched for the future benefit of all our fans."
He added: "The biggest thing is probably going to be the standing up.
"Nobody is asking fans not jump up and down when a goal is scored, but if they do not remain seated during the quieter periods of the game it could have a detrimental effect.
"It could be that capacities for future games will be reduced which will cost fans the chance to be there and stop revenue coming into the club."
Source SWWP.CO.UK by Gareth Vincent