The autopsy was performed shortly after the 31-year-old was found dead in his home in Milton, Massachusetts, but the family only got to see it a few days ago.
In an interview with the Boston Globe, widow Kristen and father Kevin tell about the incident in the hope that a similar tragedy can be avoided.
"I'm stuck"
Hayes, with 334 NHL appearances in Florida, Boston and New Jersey, among others, ended his ice hockey career after the 2018/19 season.
Shortly afterwards, Kevin Hayes saw how his son changed and confronted him.
- He had an injury for a while and started taking painkillers.
I said "Jim, I see a problem here".
I myself am a former addict and know how powerful these things are.
So I said, "When you want help, I'm here for you, buddy."
He continues:
- He called me three weeks later and said "dad, I'm stuck on these pills and can not stop".
We made sure he got help and I thought he got out of it, but this is strong stuff.
Received strong criticism
On August 23, 31-year-old Jimmy Hayes passed away.
The NHL has recently been criticized for the clubs being too generous in dispensing prescription drugs.
Something that, among other things, Swedish NHL goalkeeper Robin Lehner testified about.
Now the Hayes family hopes that the son's death can lead to change.
- I hope Jimmy's story can save someone's life.
If this can save someone from the pain, it's good.
It's just so sad.
I'm proud to be mentally strong, I'm a guy from the street.
But there is no recipe for this, says Kevin Hayes.