The Strictly Come Dancing professional appeared on Friday's show to discuss what she's been up to during lockdown.
However, as Eamonn and Ruth Langsford introduced her, he apologised after saying her name incorrectly.
He said: "Very shortly, she's been keeping us dancing in lockdown but will she be able to defend her winning title this year?
"There she is, she's my favourite and she knows it," as Oti waved on video call from her home in London.
There she is, she's my favourite and she knows it.
Eamonn added: "It's Strictly professional, Oti Matuse," as the dancer laughed.
Ruth said: "Oti Mabuse. You're thinking of her sister as well."
Eamonn replied: "Sorry, I was thinking about his sister."
Viewers mocked Eamonn for his mistake on Twitter.
One person said: "Eamonn's favourite from Strictly, but he doesn't even know her name."
Another wrote: "Get her name right."
A third added: "Eamonn just called her Oti Matwose."
Meanwhile, Eamonn recently admitted he fears he has four years left to live after his dad died aged 64.
Speaking on The Journey podcast, he said: "My father was dead at 64. He died of a heart attack. That gives me four years.
"Ruth says, 'Don’t talk like that,' but you do think like that."
Eamonn later revealed he still has dreams he'd like to pursue, despite his longstanding TV career.
The star added: "There’s projects that I crave and I’ve got interests in lots of things.
"I’m not a superhuman. But I have a positivity, a lust for life. I don’t feel that I want to slow up."
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