Police have accused a 17-year-old player in a recreational soccer league of punching Portillo after the man called a foul on him and issued him a yellow card.
"The suspect was close to Portillo and punched him once in the face as a result of the call," Hoyal said in a press release.
The teen has been booked into juvenile detention on suspicion of aggravated assault.
Hoyal said authorities will consider additional charges since Portillo has died.
He said an autopsy is planned. No cause of death was released.
Portillo suffered swelling in his brain and had been listed in critical condition, Dr. Shawn Smith said Thursday at the Intermountain Medical Center in the Salt Lake City suburb of Murray.
The victim's family, which publicly spoke of Portillo's plight this past week, has asked for privacy, Hoyal said. Johana Portillo, 26, said last week that she wasn't at the April 27 game in the Salt Lake City suburb of Taylorsville, but she said she's been told by witnesses and detectives that the player hit her father in the side of the head.
