A vendetta born of a soured business deal in the world of motor racing led to the killings of legendary driver Mickey Thompson and his wife Trudy nearly two decades ago, a prosecutor told jurors during opening statements in a murder trial.

With the prosecution's case relying heavily on circumstantial evidence, witnesses testified Monday that defendant Michael Goodwin had bitterly spoken of killing Thompson, his former business partner.

Goodwin's lawyer said no physical evidence or witness puts her client at the crime scene or links him to arranging the Thompsons' killings.

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One witness, Bill Wilson, said Goodwin made a threat that stunned him during a dinner party more than a month before the shootings.

"'Thompson is killing me. He's destroying me. He's taking everything I've got,"' Wilson quoted Goodwin as saying. "'I'm gonna take him out."'

Wilson, a former police commander who had gone into managing stadiums where Thompson and Goodwin staged their motocross and supercross races, said he protested to Goodwin: "Nobody wins that one. Mickey's dead and you're in prison."

Wilson's wife, Nina, who followed him to the witness stand, said she overheard the conversation. She said that when Wilson told him he would go to jail, Goodwin responded, "Oh no, I'm too smart for that. Nobody will pin it on me."

Goodwin, 61, is charged with two counts of murder with special circumstances and faces life in prison if convicted. The trial was scheduled to continue Tuesday.

The racer, who was 59 when he died, was the first person to travel more than 400 mph on land. He was inducted posthumously into the Motorsports Hall of Fame of America.

Prosecutors contend the evidence leads directly to Goodwin, a former concert promoter who merged his motocross racing business with Thompson's before the pair had a falling out. They say Goodwin became so angry after losing $793,000 to Thompson that he set out to kill him.

Thompson and his 41-year-old wife were leaving for work in March 1988 when they were ambushed outside their home in the gated Los Angeles suburb of Bradbury.

Two men who shot the couple and fled on bicycles were never caught.

Defense attorney Elena Saris said Goodwin was a victim of false assumptions, and that TV shows created a "folklore" that prompted people to come forward with unsubstantiated accounts.

"This is the story of a botched investigation and a Hollywood series of events based on false assumptions," Saris said.

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