Deep Purple took the stage on Aug. 28, 1970 at the Jam Factory in San Antonio. Missing from their lineup was prolific guitarist Ritchie Blackmore, replaced on this night by Christopher Cross.

Cross would later earn fame as a soft-rock balladeer, but he cut his teeth on the Texas live circuit. Then just 19 years-old, Cross had already earned a reputation among local musicians as an excellent guitar player.

Deep Purple had been instructed to get flu shots prior to their San Antonio show. While most of the band got their vaccinations without incident, Blackmore responded poorly to the inoculation and became severely ill. With their guitarist unable to perform, Deep Purple needed a fill-in.

"They didn’t really want to cancel the show if they could help it,” Cross recalled in the book The Yacht Rock Book: The Oral History of the Soft, Smooth Sounds of the 70s and 80s. A local promoter named Joe Miller was handling the Purple show and also "kind of managing" Cross at the time. "And Joe Miller said, ‘Y’know, there’s this guitarist in town who’s a big fan of Ritchie’s and he could probably step in.’"

At Miller's suggestion, Deep Purple welcomed Cross to the lineup for the night. "I came down, and I had a Flying V and long hair, and I’m this big Ritchie fan. So we played the songs that I knew and then we jammed some blues. And they told the crowd Ritchie wouldn’t be there. It was a great moment for me," Cross admitted. "And then, when they left town, I went to the airport and got to meet Ritchie, and he thanked me for covering for him. He was cool."

As luck would have it, Deep Purple and Cross shared the same record label decades later. When the company’s boss asked Jon Lord about the night Cross sat in with the band, the Deep Purple keyboardist insisted it never happened. Stunned, Cross sought out his longtime friend Eric Johnson for verification.

"I called up Eric, and I said, ‘Man, is this a flashback or something? Am I imagining this?’ He goes, ‘No way. I was there. We opened and you played with them. Jon Lord’s lying,'" Cross explained. "This is something that Jon Lord wanted to forget and I wanted to remember. Because it was a nightmare for them. It was just horrible. ... And their star, Ritchie, was a pretty big part of it. But it’s a very cool thing."

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