All weekend football in Italy was called off following the death of Livorno midfielder Piermario Morosini on Saturday, the Italian Football Federation said.
The 25-year-old, on loan from Serie A side Udinese, collapsed on the pitch during a second division game at Pescara and was later pronounced dead in hospital.
Morosini's death comes just under a month after Bolton Wanderers midfielder Fabrice Muamba suffered a cardiac arrest during his side's FA Cup quarter-final match with Tottenham, prompting calls for more stringent medical checks on footballers.
The Italian Football Federation general manager Antonello Valentini responded to Saturday's tragedy by suspending all remaining weekend football, starting with the Serie A match between AC Milan and Genoa.
The match had been due to kick-off at 6pm local time.
Fans already at the San Siro stadium responded to that announcement largely with applause, although some jeered.
Italian Olympic Committee president Giovanni Petrucci later invited all Italian sports federations to observe a minute's silence in memory of Morosini.
Morosini suffered a suspected heart attack during the first half of the match. He collapsed suddenly and was treated on the pitch before being taken away by ambulance to the Civile Santo Spirito hospital in Pescara. But he was later pronounced dead.
The player, a former Italy under-21 and youth international, had been conscious when put in the ambulance but his condition was said to be serious when he arrived at hospital.
"He looked me in the eyes when he entered the vehicle," Pescara chief executive Danilo Iannascoli told Sky television.
"Morosini fell, he tried to get back up but fell again. Our masseur realised what was happening."
Iannascoli also said the ambulance was blocked from coming onto the pitch due to a vehicle parked in front of an exit, leading to players carrying Morosini on a stretcher out to the ambulance.
Pescara goalkeeper Luca Anania explained: "There were moments of great confusion and I tried to understand what was happening, also with regard to the delay of the emergency services.
"They said the ambulance couldn't come onto the pitch because the entrance was blocked by another car.
"Some of my team-mates carried the stretcher to the ambulance."
News agency ANSA said the car blocking the exit was a police vehicle, however a heart specialist said the delay made no difference.
"A minute more or less in the ambulance would not have done anything," said the cardiologist Dr Paloscia.
"His heart had stopped and never started beating again.
"We tried to reanimate him for an hour and a half but it was all to no avail."
Italian media were alerted to Morosini's death initially by an "explosion of shouts and tears" from his teammates who had come to the hospital, ANSA said.
Police started to usher the press away but the official confirmation followed shortly afterwards.
Image: Livorno players look on as they stand on the touchline after team-mate Piermario Morosini suddenly collapsed (Getty Images)