Jimmy Hayes died with fentanyl and cocaine in his system, according to his widow Kristen and father Kevin Sr. who spoke with The Boston Globe on Sunday.
The medical examiner also confirmed to PEOPLE that Hayes' cause of death was acute intoxication due to the combined effects of fentanyl and cocaine. His manner of death was determined to be accidental.
On Friday, when Hayes' death certificate was issued to the town hall in Milton, Massachusetts, the Norfolk County District Attorney's office confirmed to PEOPLE that no foul play was involved in Hayes' death.
That same day, Kristen and the Hayes family learned of the cause of death prior to attending the New Jersey Devils' season opener against the Chicago Blackhawks at the Prudential Center, where both teams paid tribute to Hayes. (The Devils wore No. 10 with Hayes' Broadway nickname on the back and the Blackhawks wore Hayes' No. 39 sweater during warmups. The late star was recognized in a tribute video.)
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Hayes, a 31-year-old native of Dorchester, was pronounced dead by first responders at his Milton home on Aug. 23. The evening prior to his death, Hayes and his wife of three years Kristen celebrated their son Beau's second birthday with their son Mac, who was born on May 5.
Hayes' autopsy was completed on Aug. 25, but at the time, the medical examiner's office said the "cause and manner of death remain pending and an update is not expected for several weeks when toxicology testing comes back," in a previous statement obtained by PEOPLE.
"I was completely shocked,'' Kristen told the Globe after getting the toxicology report from the Massachusetts state medical examiner on Friday.
"I was so certain that it had nothing to do with drugs. I really thought it was a heart attack or anything that wasn't that [drugs]," she said. "It didn't make any sense, so it was hard. I was hoping to get a different phone call when they called. I was hoping to get some clarity and I was shocked to hear that it was that ... He never showed any signs of a struggle at home.''
Rocky W. Widner/NHL/Getty Jimmy Hayes
According to the Globe, Hayes had a problem with pain pills when he was playing professionally.
"I'm an addict myself. I'm sober a long, long time, but I know how powerful this stuff is. I was in shock when it happened, but then I started putting stuff together in my head," his father Kevin Sr. told the outlet, adding that his son "made a terrible mistake and it cost him his life."
"About maybe 16 or 17 months ago, I saw a little change in Jimmy's behavior and I went to him and I said, 'I think there might be a problem here with pills.' He had had an injury for a while and I think he started taking the painkillers and they get you," he continued, sharing that Jimmy told him: "Dad, I'm hooked on these pills. I got injured and I started taking them and I never got off."
Kristen also told the outlet: "I know he would give anything to still be here with us today. I am heartbroken and devastated, but I will choose to remember my husband and the boys' dad by all the joy and love he brought us, and I hope everyone else does, too.''
A week following his death, on Aug. 30, hundreds gathered at St. Ann's Church in Dorchester to pay their respects at Hayes' funeral.
A procession of youth athletes, who dressed in Dorchester Youth Hockey jerseys, lined the local streets to honor their hometown hero before the service started. In attendance were Kristen and their respective parents as well as family members and friends. Jimmy and Kristen's two young sons, Beau, 2, and Mac, who was 3 months old at the time, were not at the funeral.
Another heartbreaking speech at the funeral was made by Hayes' younger brother Kevin Hayes, who plays for the NHL's Philadelphia Flyers. "He made me the best version of myself," said Kevin, who fought back tears while addressing those in attendance.
Describing his older sibling as a "caring, loving, generous, loyal and determined" loved one, he continued, "As a brother, he built us up every way he could. He brought joy and laughter into every interaction."
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Kevin Hayes shared this beautiful story at his brother Jimmy’s funeral. pic.twitter.com/jkVosgLNmo
— TSN (@TSN_Sports) August 30, 2021
Following news of his death and ahead of the 2021 season, the NHL shared a highlight reel from Hayes' seven-year career in the league. "We'll always remember you, Jimmy," the video was captioned.
Hayes played 334 games for four teams after a successful collegiate career and NCAA championship at Boston College.
In 2008, he was drafted 60th overall by the Toronto Maple Leafs and made his NHL debut with the Chicago Blackhawks in 2011. Two years later he was traded to the Florida Panthers and eventually played for his hometown club Boston Bruins in 2015. Hayes finished his professional career with the New Jersey Devils in 2018.
In his post-NHL career, he was a co-host of the Missin Curfew podcast and his last recorded show was in August. Following his death, the podcast released a special episode, titled "The Best of Jimmy Hayes," on Sept. 2.
Hayes is survived by his wife Kristen and their two sons as well as his parents Shelagh and Kevin Sr. and siblings Genevieve, Eileen, Justine and Kevin.
If you or someone you know is struggling with addiction, please contact the SAMHSA substance abuse helpline at 1-800-662-HELP.