Eagle-eyed fans, however, were convinced that they spotted a well-known star from another show entirely.
One tweeted: "Is that Curtis Pritchard in the white jeans and blue shirt???"
Coronation Street and Emmerdale actress Sally Ann Matthews had the same thought, tweeting: "Is that Curtis?? x #strictly."
Another viewer wrote: "Yay @bbcstrictly time, anyone else think one of the pro dancers was @CurtisPritchard in the opening number? Don’t think I watched the dance, too busy trying to see if it was him…"
WATCH: Dawn French clarifies flippant Strictly Come Dancing remark
They were soon informed, however, that the background dancer wasn't the Love Island contestant but former Britain's Got Talent star Kai Widdrington, who the BBC signed up after being impressed by his skills.
In theory, it wouldn't be that strange for Curtis to have appeared on Strictly, considering the fact that he is a dancer and choreographer who has appeared on the Irish version of the show, Dancing with the Stars.
It would also continue a proud family tradition, as Curtis' brother A.J Pritchard was on Strictly for four years, dancing with celebrity partners Claudia Fragapane, Mollie King, Lauren Steadman and Saffron Barker.
Curtis' brother AJ was a regular on Strictly
The 25-year-old announced his departure back in March, however, sharing that he hoped to move on to new opportunities, inspired by his brother.
A statement from his agent at the time read: "After four years on Strictly Come Dancing, AJ has decided the time is right to leave the show and follow his dreams to explore opportunities in the presenting world alongside his brother Curtis."
Saturday night's programme was the first time the new round of celebrities got to strut their stuff in front of a live audience.
Boxer Nicola Adams, DJ Clara Amfo, and EastEnders star Maisie Smith among those winning praise from judges Shirley Ballas, Craig Revel Horwood and Motsi Mabuse.
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