Just like every rock and roll band, Queen had to prove their worth as concert openers before graduating to headliner status. And that’s precisely what Freddie Mercury, Brian May, John Deacon and Roger Taylor were doing on the night of April 16, 1974, when they made their U.S. concert debut in support of Mott the Hoople.

Queen’s debut album had performed modestly and their sophomore, titled Queen II, had only been delivered to American record stores just three days earlier – about one month after its U.K. release. So, they were still, by and large, unknowns in the new world.

That meant Queen was effectively starting from scratch as they stormed the stage at Denver's Regis College, a conservative Jesuit institution, in an effort to change this state of affairs — one show, and even one fan, at a time.

Luckily, Queen enjoyed close friendships with the men of Mott (the two bands having already toured extensively together back home), and so the latter did not mind that their upstart openers already pranced and posed upon the stage like well-established superstars. In fact, Mercury and May cut quite striking visions in the lavish silk and satin costumes that were custom-designed in all black for Freddie and all white for May (in reference to Queen II’s “black” and “white” vinyl sides) just prior to the tour by band friend Zandra Rhodes.

Queen’s set, likewise relied heavily on their latest album, at first, powering up with "Procession," "Father to Son," "Ogre Battle" and "White Queen (As it Began)," before segueing into select first-album highlights like "Great King Rat," "Doing Alright," "Son and Daughter" and "Keep Yourself Alive" (plus the never officially released "Hangman"), before concluding with "Seven Seas of Rhye" and finally, the explosive "Liar."

Meanwhile, the audience was initially fairly stunned into wide-eyed silence by Queen’s arena-sized display of heavy-rock opulence, according to eyewitness reports. But they were clearly won over by set’s end, because they shouted the band back on stage for not one, but two encores, which Queen devoted to vintage rock covers ("Jailhouse Rock," "Shake, Rattle & Roll") and, oddly, cabaret stomps through Connie Francis’ "Stupid Cupid" and Shirley Bassey’s "Big Spender," before demolishing the stage with the frantic onslaught of "Modern Times Rock ’n’ Roll."

Obviously, headliners Mott the Hoople had their work cut out for them that night, and throughout the ensuing, month-long tour. But sadly, everything ended prematurely for the members of Queen, when Brian May was taken ill with hepatitis and ordered to recuperate at once.

Back home to England they went, undoubtedly disappointed that their American assault had been suspended for the moment – but also confident that that country’s first impression of their band had been both positive and promising. Many triumphs were waiting in the next few years.

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