Brighton & Hove Albion chief executive Paul Barber tells BBC Sussex that there is no room for major expansion at the Amex Stadium if the club reaches the Premier League.
Already the promotion-chasing Championship side, who are just one point and two places outside the top six, have sold more than 21,000 season tickets for next season.
Last term, in what was their second season playing at the £93 million ground, the Sussex club recorded the highest average attendance in the Football League.
Since first moving to the stadium at Falmer in 2011, a further 8,250 seats have been added to increase the ground's capacity to 30,750.
Albion's record attendance was 36,747 at their old Goldstone home against Fulham in the old Division Two in December 1958.