The rock bills of the '70s often had more to do with label considerations and promotional logistics than any thought of putting together artists that might have made a good musical fit. It produced some pretty bumpy tours for opening acts forced to play to hostile or indifferent crowds, but in retrospect, it led to some unforgettable bills — like the night Judas Priest played their first U.S. gig as an opener for REO Speedwagon.

Priest, touring at the time behind their third album, Sin After Sin, had yet to break into the American market — and it would take them some time, with their hard-fought U.S. breakthrough not arriving until 1980's British Steel. That journey started in earnest on June 17, 1977 in Amarillo, Texas, and although they might not have picked up many new fans in the crowd, it's a night REO Speedwagon frontman Kevin Cronin still remembers — and one he recently reminisced about with Priest singer Rob Halford.

"I did a TV show with Rob Halford a couple of weeks ago. It was a Comedy Central show," Cronin told Ultimate Classic Rock's Matt Wardlaw. "It was kind of a cool thing where different comedians kind of go up and do a little bit on a band and a certain song that affected them and affected their comedy and then the actual artist comes out and you do a little duet with them. It was a lot of fun."

After doing their bits, Cronin and Halford met up backstage, where they bonded over that long-ago show. "I probably haven’t seen the guys since then, so it’s 40 years later. I was walking off stage and he was coming on next," said Cronin. "I’m like, 'Dude, you guys...we did some dates together a long time ago, didn’t we?' And that’s when he told me, he goes, 'Yep! We did our first American shows opening for you guys.'"

As Cronin recalls it, Judas Priest were still being marketed as a "straight-ahead rock band" at the time, and wouldn't debut their signature look for a little while yet. Uncertain image notwithstanding, Cronin heard an energy that inspired him in Priest's set.

"The next time I saw them, they kind of came out with the leathers and this whole kind of new vibe that they had. It was different than the Judas Priest that I remembered when they were playing with us. But they were strong and they were a powerful band," said Cronin. "I always liked when the band that went on before us was good. Because that just lit a fire under us. Judas Priest definitely lit a fire under us."

Since parting ways as tourmates, the two groups have obviously continued to follow very different paths — but, as Cronin laughingly noted, they can both be proud of their achievements. "I think they’ve done pretty well since then," he quipped. "I think their career kind of panned out a little bit, didn’t it?"

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