As fixtures in Italian football were called off for the weekend as a mark of respect, key figures from the Italian game paid tribute to midfielder Morosini.
"I do not know what to say, thinking of a friend and colleague dying on a football pitch like that," Juventus and Italy midfielder Claudio Marchisio.
"He was an amazing guy. We were in the under-21's together. Piermario, we'll miss you a lot."
""There is huge grief," added Inter Milan defender and friend Andrea Ranocchia. "It leaves an enormous hole."
The 25-year-old, a former Italy under-21 international who was at Udinese until January, was pronounced dead on arrival at hospital, having suffered an on-field collapse.
He had fallen to the ground in the 31st minute of the match, and despite the efforts of medical staff at the ground and from the emergency services, did not recover.
"Wearing the colours of Livorno, Piermario always showed his athletic ability and that he was an exceptional man," his club said in a statement. "Everyone at Livorno expresses the most sincere condolences to his family."
Luca Anania, in goal for Pescara during the match, spoke of his shock as events unfolded.
"When the referee stopped the game we all came close and understood," he said. "We were all shocked, then we found out the lad did not even have any parents."
Morosini had been orphaned by the time he was 17, with his mother dying in 2001 and his father passing away a couple of years later.
His disabled brother committed suicide shortly after his father’s death, and Piermario is survived only by his older sister, who is also disabled.
"It's an incredible destiny, now he can embrace all his family," said former team-mate at Udinese Roberto Baronio.
Despite the setbacks, Morosini, who had reached the Italian under-17 team at just 15, showed a determination to succeed in the sport.
"These are things that leave an impression on you and change your life," Morosini said in a 2005 interview.
"But at the same time it fills you with anger and helps you to always give everything to achieve what was also my parents' dream.
He added in an interview: "I would like to become a professional footballer mainly for them because I know how much it would make them happy and for that I know that I have extra motivation."
The decision to suspend football in Italy was supported by the Italy national coach Cesare Prandelli.
"To stop the championships was a decision of common sense and civility," Prandelli said, "but I'm not worried about all these deaths in the world of sport. It is only individual cases, the statistics do not seem alarming."
The death comes just four months after Italy was rocked by the death of popular MotoGP rider Marco Simoncelli who suffered a fatal crash at the Malaysian Grand Prix aged just 24.