Phoenix, 31, who is nominated for his starring role in "Walk the Line," was driving through the canyon last Thursday when his brakes went out. He swerved into the mountainside to avoid hitting another car, the driver's side air bag deployed and the vehicle flipped upside down, he told the Los Angeles Times.
Feeling "a bit confused," he heard knocking on the passenger side window.
"There was this German voice saying, 'Just relax,'" Phoenix recalled. "There's the air bag, I can't see and I'm saying, 'I'm fine. I am relaxed.'
"Finally, I rolled down the window and this head pops inside. And he said, 'No, you're not.' And suddenly I said to myself, 'That's Werner Herzog!' There's something so calming and beautiful about Werner Herzog's voice. I felt completely fine and safe. I climbed out."
The director who won the Directors Guild Award for his 2005 documentary "Grizzly Man," lives near the accident scene, the Times said.
"I got out of the car and I said, 'Thank you,'" Phoenix told the newspaper. "And he was gone."