I didn’t discover Elvis until the early Seventies when he was that big sweaty guy with huge sideburns in the white rhinestone-studded jumpsuits singing overblown ballads on a stage in Vegas.

And while the Sun Sessions from 15 years earlier, which I wouldn’t discover for decades, have come to occupy a place deep in my heart, I have come to love the Vegas Elvis that I once mocked for those very same mutton chops and jumpsuits.

Especially this period around 1970 when he recorded live versions of The Wonder Of You – a chart-topper in the UK and USA in 1970 – and, six months later, the equally magnificent, arguably even greater, I Just Can’t Help Believing.

It was only a single in the UK – plucked from the the album That’s The Way It is, which mixed four live tracks with eight studio ones. But wow! Just wow!

It’s the essence of Elvis the Vegas performer: the maestro guiding his band, and his backing singers, like a classical conductor; building the song up from that minimalist intro, ushering in the horns to echo the melody, then slowing it all down again for the backing singers.

If you study his face, you can see him inhabit​ the song, living the emotions. That was Presley’s gift – without writing a single song, he understood every word of the lyrics and sang them as if the experience was his own. He made​ them his own.

It always makes me well up when he sings the line about how she slips her hand in his, “and it feels so small and helpless, and my fingers fold around it like a glu-uh-uuhve.”

The call-and-response with the backing singers is what the song is all about. “This time the girl is gonna stay,” he croons, and the girls sing it back to him. “For more than just a day-ay-ayy,” Elvis replies, hope turning to expectation.

And then the brass comes in with a fanfare that seals the deal, only to subside as Elvis turns to check with the girls that it’s really going to happen. , “Sing the song baby,” he encourages them. “One more time… One more.” And they do. And then they fade away almost to complete silence, and then he comes back again: “For more than just a day.”

It’s just glorious. And then they do it all over again. And of course he winds it all up with one of those whirling arm movements and a judo move.

And because I didn’t know back then that Elvis didn’t write his songs, I didn’t know that this one was originally recorded by someone called Barry Mann (who wrote it with his wife Cynthia Weil) in 1968, or that it had been a US hit for a Christian country singer called BJ Thomas in 1970.

And, bizarrely, in 1969 by Leonard Nimoy.