Flowers, club scarves, football boots and banners with messages such as "Ciao Moro, you will always be in our hearts" hung on the railings outside the modern church in the Monterosso district of Bergamo where Morosini grew up.
Thousands of people applauded and touched Morosini's coffin as it was carried out of the church, draped in his number 25 red Livorno shirt. Morosini, a former Italy Under-21 international, was 25 when he died.
The black-and blue number 8 shirt he wore as a youth player at his home club Atalanta was also put on the coffin as it was placed in a hearse. Fans lit flares and chanted.
"This has not only hit the family but the whole community and the whole of Italy," said Bergamo resident Gianpietro Foschi.
Morosini collapsed on the pitch during a Serie B match between Livorno and Pescara on Saturday, prompting the cancellation of all Italian championship matches last weekend.
He was rushed to hospital but doctors were unable to revive him. An autopsy failed to establish a cause of death but ruled out heart attack or aneurysm. More tests were ordered.
An inquiry has been launched into whether there were delays in trying to save Morosini's life. Controversially, defibrillators were available but were not used.
The inquiry is also looking into whether vital minutes were lost because a municipal police car blocked the entrance to the stadium, briefly preventing an ambulance getting in. Police smashed the window to move it.
Morosini's fate contrasted with the recovery of Bolton Wanderers midfielder Fabrice Muamba, who suffered a cardiac arrest during an FA Cup match in England on March 17.
He was clinically dead for 78 minutes and 15 defibrillator shocks were applied to restart his heart. He was discharged from hospital last Monday.
Morosini's death was all the more poignant because of his tragic family life. He was providing for his severely disabled younger sister after the death of their parents and the suicide of a brother, who was also disabled.
Atalanta said they would take care of the player's sister for the rest of her life.
