The Wanted star, 32, was clearly overcome with emotion as they completed their American Smooth routine on Saturday’s show.
He could be heard yelling: ‘F**king get in!’ when their dance ended, just before judges dished out their critiques.
Taking to Twitter, the Glad You Came singer admitted he got ‘lost in the moment’ and accidentally dropped the F-bomb.
As you do.
‘Hope you enjoyed the dance guys!!!! I may have got a little bit lost in the moment and said a bad word,’ he tweeted.
‘Apologies if that was the case! Much love!!! X.’
Viewers couldn’t get over the scenes, rushing to discuss the swear on social media.
‘”F**king get in” MAX THIS IS A FAMILY SHOW,’ one wrote, while another said: ‘I’m sure I just heard Max say ‘f**king get in’ at the end of that dance.’
‘Did Max just say what I think he said,’ a fan questioned.
Claudia Winkleman addressed the expletive later in the episode, telling everyone watching from home: ‘I also just want to quickly apologise for some language earlier that involved Max.
‘I don’t know the details, I don’t know if you heard. If you did, we’re deeply sorry.
‘Even if you didn’t hear, we’re sorry on every level.’
Swears aside, Max and Dianne earned a respectable 20 for their dance, which was set to It Had To Be You by Harry Connick Jr.
Craig Revel Horwood opted to give them a score of five, while Shirley Ballas was a little more generous, offering a seven, and temporary judge Anton du Beke handed the pair an eight.
Strictly Come Dancing continues on Sunday, at 7.25pm, on BBC One.
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