In a newly recovered interview from 1997, O.J. Simpson is heard airing out his grievances about how his infamous 1995 murder trial was covered -- and who benefited. "I just thought it became such a money maker for the tabloids," he said at the time.

"A lot of people got rich," Simpson said at the time. "Virtually every participant except me seems to have gotten rich."

WATCH: Marcia Clark on Knife Allegedly Found at O.J. Simpson's Estate

The practically lost interview was conducted by two Pepperdine University students -- Tommy Lee and Mindy Thomas -- who visited the Hall of Fame running back at his Rockingham Avenue estate in Brentwood, California, and then aired their report only on university television. Lee and Thomas have now shared the video exclusively with ET.

In the interview, Simpson seems to suggest that media outlets were distracted by the celebrity aspect of the trial as opposed to focusing on solving the murders of Simpson's ex-wife, Nicole Brown Simpson, and her acquaintance, Ron Goldman.

"It had a lot of elements of, you know, attractive people, well-known celebrity, money, sex appeal," Simpson said.

"I thought the media let the American public, as well as myself, down, as well as Nicole and Ron down in trying to find the true perpetrators," Simpson said in the interview.

WATCH: Knife Allegedly Found at O.J. Simpson's Estate, LAPD Confirms

The release of this footage comes as Los Angeles police begin investigating a knife that was allegedly recovered on property once owned by Simpson.

"It's a remarkable development if it does turn out to be connected to the murders of Ron and Nicole," attorney Marcia Clark, who was the head prosecutor during Simpson's trial, told ET exclusively on Friday. "I just hope the truth comes out about the situation."