The actor was involved in an accident with a snowplow in January.
Rich Kovatch tells ABC News' Diane Sawyer that he and his partner, Barb Fletcher, were the first people on the scene of the accident, and recalls the aftermath of the near-fatal accident.
"It was the blood, the amount of blood, he was just in so much pain and the sounds that were coming out of him," Kovatch tells Sawyer in a sneak preview for the ABC News special with Renner and others. "There was so much blood in the snow, and then when I looked at his head it appeared to me to be cracked wide open and I could see white. I don't know if that was his skull, maybe it was just my imagination, but that's what I thought I saw."
In January, Renner was crushed by a snowcat near his home in the Mt. Rose Highway area of Reno, Nevada. According to a redacted Washoe County Sheriff’s Office incident report obtained by ET, Renner towed his nephew's vehicle after it got stuck in the snow. In the process, the snowcat began to move, and Renner tried to prevent his nephew from being hurt.
Fletcher revealed that she rushed outside with a folded towel and administered pressure to Renner as he laid in the snow in pain.
"I could tell he was really struggling to breath," she says.
Also on the scene was Renner's nephew, Alexander Fries, who says he stayed by his uncle's side through the entire ordeal.
"Just breathe, just breathe, that's it," Fries says he told his uncle. "And I stood over him in this crouched position holding his arm for the entire time. From seconds when that guy came over, I was just locked in on that."
While he was in the hospital, Renner had the support of his mother, Valerie Cearley, who becomes emotional as she talks about her son's condition.
"He was intubated," she says through tears. "He was out ... his breathing was horrible."
The Hawkeye star shares that while he was in the hospital, his mother read Stephen King to him as he went through his healing process.
"It happened to be what I was reading at the time," Cearley says. "I just wanted him to hear my voice."
Renner -- who broke 30 bones in the accident -- says that through it all, he survived with the love of his family and strength. He is adamant that he is not a victim.
"I shift the narrative of being victimized or making a mistake or anything else," he tells Sawyer. "I refuse to be haunted by that f**king memory that way. This is what I talk to my family about, from all their perspectives, which is horrifying. That I put upon them, what we just endured, that's real love. Suffering but that feeds the seeds of what love is."
Jeremy Renner, The Diane Sawyer Interview: A Story of Terror, Survival and Triumph airs Thursday at 10 p.m. ET.