Donnovan Hill, who was paralyzed during a Pop Warner football game in 2011 at the age of 13, died Wednesday after complications from surgery.

According to a report by ESPN’s Tom Farrey, Hill, 18, was admitted to the hospital Tuesday for a routine surgery on his lower back to manage his injury. Hill’s mother, Crystal Dixon, told Farrey she was told that during the surgery, the doctor accidentally cut an artery, and Hill fell into a coma as he lost blood. He died Wednesday at 4:35 a.m., Dixon said. Hospital spokespeople were unavailable to confirm details of Hill’s death to ESPN.

Hill’s last tweet before surgery urged followers to pray for “Vizzy,” one of his nicknames.

Related: Judge: Paralyzed Player’s Case Against Pop Warner Can Proceed

Hill, from the Los Angeles suburb of Lakewood, Calif., was paralyzed from the neck down after a hit on the goal line during a regional Pop Warner championship game. Hill later said he used a headfirst technique that his coaches promoted. The hit left Hill with minimal use of his arms and no movement below his chest.

Hill’s family reached an undisclosed seven-figure settlement with the Pop Warner national office in January, one month after a California judge ruled that Hill’s lawsuit against Pop Warner could go to trial. Pop Warner had argued that the lawsuit should be dismissed because Dixon had signed a waiver acknowledging the dangers of playing football and the potential of serious injury. Judge Frederick Shaller ruled that the waiver does not protect Pop Warner from claims of gross negligence. The trial date, ironically, had been scheduled for May 11, the day Hill died.

After ESPN aired Hill’s story in 2015, strangers donated a motorized wheelchair and handicap-accessible van to assist Dixon and Hill. Last month, they moved out of her mother's apartment and into their own apartment in anticipation of the settlement funds becoming available, ESPN reported. Dixon said she has not received any of the settlement money to date.

“Donnovan’s case will have an impact on young athletes for generations,” said Rob Carey, Hill’s lawyer. “It will help ensure that those in charge of safety — from directors and coaches to whole organizations — will not be allowed to shirk their duties or avoid responsibility.”

A wrongful death suit that was filed in federal court in Wisconsin in 2015 seeking $5 million in damages was settled in February for an undisclosed sum. The family of a former Pop Warner football player who committed suicide at 25 blamed Pop Warner for their son suffering from the degenerative brain disease chronic traumatic encephalopathy (CTE) as a result of suffering head trauma.

Hill’s death comes the same week that Pop Warner announced it is eliminating kickoffs for its three youngest divisions in an effort to make the game safer.

Related: Could Pop Warner Settlement Signal the End of Football?