Southampton were expelled from the Championship playoff final on Tuesday by the English Football League after spying on a training session of semifinal opponents Middlesbrough.
Middlesbrough have been reinstated and are set to face Hull at Wembley on Saturday for a place in the Premier League.
Southampton will also be docked four points next season after admitting to multiple breaches of regulations related to the "unauthorised filming of other clubs' training" sessions, according to a statement from the English Football League.
"An independent disciplinary commission has today expelled Southampton from the Sky Bet Championship playoffs," the EFL said.
Southampton, relegated from the Premier League last season, confirmed they would appeal the sanctions.
The EFL said the parties were working to ensure an appeal could be heard on Wednesday.
"Subject to the outcome, it could result in a further change to Saturday's fixture," the EFL said.
Promotion to the Premier League is worth an estimated £200 million in extra revenue.
A member of the Southampton coaching staff was caught by Middlesbrough officials recording training on his phone.
The EFL confirmed further charges had been laid against Southampton, and that the club had also admitted observing training sessions ahead of matches against Oxford and Ipswich.
The first leg ended 0-0 before Southampton progressed with a 2-1 win after extra-time in the second leg.
Middlesbrough issued a statement welcoming the outcome of the disciplinary commission hearing.
"We believe this sends out a clear message for the future of our game regarding sporting integrity and conduct," it said.
A statement from MFC:
— Middlesbrough FC (@Boro) May 19, 2026
Middlesbrough Football Club welcomes the outcome of today’s Disciplinary Commission hearing.
We believe this sends out a clear message for the future of our game regarding sporting integrity and conduct.
As a club, we are now focused on our game against… pic.twitter.com/6cjskjZKDY
Southampton have lost just once in their last 25 games, a 2-1 FA Cup semifinal defeat to Manchester City.
After a poor start to the season, they stormed into contention for promotion once Tonda Eckert took charge in November.
However, the future of the German coach at St. Mary's is now in doubt.