When an audio recording, made surreptitiously just after the incident on Sept . 13, 2007, was played in court on Tuesday, Mr. Fromong, 54, acknowledged that it was his voice that was heard saying: “I’ll have ‘Inside Edition’ down here tomorrow. I told them I want big money.” Earlier in the day, pressed by Mr. Simpson’s defense lawyer, Gabriel Grasso, Mr. Fromong had denied making precisely that statement.

Mr. Simpson, 61, is charged with 12 crimes including armed robbery and kidnapping in connection with the incident, in which he and a group of five men entered a room at the Palace Station Hotel-Casino for six minutes. They left the room with memorabilia connected mainly with the careers of three former star athletes: the football players Joe Montana and Mr. Simpson and the baseball player Pete Rose.

Mr. Fromong and a fellow collectibles dealer, Alfred Beardsley, who had the memorabilia, were told by a third dealer, Thomas Riccio, that potential buyers would visit the hotel room to browse the goods, but it was Mr. Simpson and his associates who appeared and took the goods.

The case turns in part on the rightful ownership of the memorabilia. Mr. Simpson has insisted that he was retrieving personal keepsakes previously stolen from him, and that he was unaware that any of his associates had brought guns with them or had brandished them during the encounter in the hotel room. His defense team is attempting to paint Mr. Fromong, Mr. Beardsley and several other men involved in the incident as profiteers who knew the items rightfully belonged to Mr. Simpson and hoped to cash in on the media fascination with all things Simpson.

Mr. Riccio, a convicted felon who has said that he set up the encounter to help Mr. Simpson recover the items, recorded the incident and sold excerpts of the audio tape to a tabloid-style Internet celebrity website.

Mr. Fromong, who began his testimony on Monday afternoon, said that someone in the room during the chaotic encounter shouted, “Put the gun down,” an assertion that suggested Mr. Simpson was aware of the presence of weapons.

Mr. Grasso said on Tuesday that Mr. Fromong had never before mentioned such a remark on the record — not when he was questioned twice by police, nor during his testimony at a preliminary hearing in November when Mr. Simpson was bound over for trial.

Mr. Fromong countered that he had told investigators about the remark in meetings held since then. He said he had been on the phone with a friend when Mr. Simpson’s group entered the hotel room and that his friend remembered hearing the gun remark as well.

Four of the five men who accompanied Mr. Simpson have accepted plea deals and are expected to testify for the prosecution in Mr. Simpson’s trial. The fifth man, Clarence Stewart, is being tried on the same charges as Mr. Simpson before the same jury.

Mr. Fromong, who testified emotionally on Monday about his friendship with Mr. Simpson before the incident, was asked during questioning by Clark County District Attorney David Roger why he telephoned the celebrity-gossip media immediately after the incident.

“I was angry and hurt that my best friend had just robbed me at gunpoint,” Mr. Fromong said. “I was calling because it was news.”