The teen pleaded guilty Monday to homicide by assault, a third-degree felony, and will remain in a juvenile prison facility, where he could be held until his 21st birthday.
In addition, 3rd District Juvenile Judge Kimberly Hornak ordered the teen, who is not being identified by The Salt Lake Tribune because of his age, to keep a photo of the 46-year-old Portillo, who was volunteering as a soccer referee, on his wall until he is released.
The teen also must write the Portillo family members one letter a week, updating them on everything he has been doing to improve himself and explaining how he will make sure such a crime never occurs again.
"The death of someone is the most serious crime," Hornak told the teen. "[Portillo's] only crime was being present to take part in an act of community service. In one moment of rage, you took away his life. You changed the life of all his daughters. You changed your life and the life of your family."
The sentence came Monday after the teen pleaded guilty in the punching death of Portillo during an April 27 soccer match at Eisenhower Junior High in Taylorsville. Portillo died after a week in a coma.
Both families were in tears by the end of the sentencing.
"We wished you had decided to take a deep breath before you did what you did," said Portillo's 21-year-old daughter, Ana, looking the teen in the eyes. "You messed up and took our dad away."
She said the teen will never understand how much pain they are in as they struggle to cope with the loss of the man who they said was their support system.
Johana Portillo, 26, recounted the sisters' last moments with their father "calling him to wake up." Their 15-year-old sister, Valeria, spent her birthday with their dad as he lay dying.
"I hope you learned your lesson," Johana Portillo told the teen.
But at the same time, Portillo's daughter said they want the teen to have a second chance to live his life, even though their father didn't get one.
The teen, somber, cuffed and dressed in an orange shirt, said he takes full accountability for his actions that day. He said he had always previously used thoughts over actions, but that April day he acted impulsively and it had a "negative outcome."
As the teen's mother cried in the front row, he told the Portillo family he was sorry.
"I acted impulsively, childish," he said. "I learned a lesson."
The teen's mother also apologized to the Portillo family through a translator.
"Sorry for what my son did to your family," she said in Spanish.
Salt Lake County prosecutor Patricia Cassell said there is never anything that could make things right in a crime like this, but she believes the resolution is fair. She said the recommendation by the experts was to keep the youth in the juvenile system rather than try him as an adult. She said prosecutors offered to take the possibility of adult court off the table in return for his plea Monday.
Community activist Tony Yapias, who was there to support the Portillo family, said the teen could have gotten probation or less time behind bars had he been tried as an adult. Cassell said she hopes the teen and society always will be reminded of the horrible outcome that came from an act of violence against a referee in a sporting event.
And Hornak praised Portillo's loved ones for their poise and dignity.
"You're not out for revenge," Hornak said, "but you're just in a great deal of pain, and you want to make sure this never happens again."
Monday marked the first time a video camera was allowed in a Utah juvenile court proceeding. It came about after a coalition of Utah media, including The Salt Lake Tribune, asked that it be permitted.