A Portsmouth fan died at Fratton Park following a medical emergency ahead of the club's Championship game against Middlesbrough on Saturday.
The match was delayed by 35 minutes as emergency services treated the man. Portsmouth, who won the game 2-1, confirmed later on Saturday that the fan had died.
"Portsmouth Football Club are devastated to report that a Pompey fan has died following a medical emergency at Fratton Park today," the club said in a statement.
"The incident happened right at the start of the game, with the referee taking the players off the pitch to allow for treatment to be administered."
"Despite the valiant attempts of the emergency services, the supporter unfortunately passed away.
"Next of kin are aware. Our sincere thoughts and condolences go out to the supporter's family and loved ones at this sad time.
"We are grateful to all the Pompey and Middlesbrough fans inside the stadium for the compassion, patience and understanding they showed in such distressing circumstances."