Led Zeppelin's Robert Plant has told a court he has no memory of watching an American band he and Jimmy Page are accused of copying when they wrote Stairway To Heaven.
The singer and guitarist Page are facing a civil trial over claims that the opening guitar riff of their classic 1971 song was "lifted" from an instrumental track called Taurus by the US group Spirit.
A lawsuit has been filed by Michael Skidmore, the trustee of Spirit guitarist Randy Wolfe - known as Randy California - who drowned in 1997 having never taken legal action over the song.
Plant, 67, told the federal court in Los Angeles that he often attended Mothers club in Birmingham in his youth but he could not remember watching Spirit at the venue in 1970.
He said he had been involved in a serious car crash with his wife and only learnt from newspaper reports that he had been at Mothers club earlier that night.
"I can't recall Spirit or anybody else playing there with the passing of time," Plant said.
He said his wife suffered a fractured skull in the car accident.
"Part of the windshield buried in the top of my head which was interesting," he said.
"I don't remember a thing."
Plant told the court he wrote the lyrics to Stairway To Heaven after Page had played some of the song to him at Headley Grange in Hampshire.
"I was trying to bring in the beauty and remoteness of pastural Britain," he said.
"It developed into something I could not imagine."
Plant said he did not think it was a "problem" that Led Zeppelin covered other bands, including Spirit, at their early gigs in the late 1960s.
"In the nest of rock and rhythm and blues, there has always been cross pollination," he said.
Page and Plant have attended each day of the copyright infringement trial, which is expected to conclude this week.
Page, 72, previously told the court he had not heard of Taurus until his son-in-law showed him a comparison with Stairway To Heaven on the internet a few years ago.
Plant, wearing a dark suit, white shirt and tie, with his hair tied back in a ponytail, told the jury he could not remember playing snooker with a member of Spirit after their 1970 gig at Mothers club.
"I did have a bad car accident," he said.
"I don't remember seeing Spirit. I don't remember playing snooker."
Page gave evidence for a second time in the trial as he was questioned about the origins of Stairway To Heaven.
He said: "The original concept I had was for a piece of music that would basically go through many moods and changes.
"Robert and I were so in sync with musical composition at that time.
"All the time the thing is accelerating and getting more intense."
Earlier, Timothy Gardner, a consultant with Joan Hudson and Co Accountants, told the court that Stairway To Heaven had earned Page revenue of 615,000 dollars and Plant 532,000 dollars before tax over the past five years.
David Worihaye, chief financial officer at Led Zeppelin's record label Rhino Entertainment, said the song had earned the company more than three million dollars in revenue and nearly 870,000 dollars in net profit since May 2011.
Economist Michael Einhorn previously told jurors that Page and Plant had received 58.5 million dollars (£40 million) from Stairway and their other Led Zeppelin works since May 2011.
Page said he decided to record at Headley Grange after hearing Fleetwood Mac had rehearsed at the estate.
The earliest surviving recording of Stairway To Heaven from Headley Grange and the final 1971 track was played to the court.
The case continues.