Following in the footsteps of Blue member Duncan James, who stood up for Lee last week on Twitter, Antony has now also decided to speak out about the way his friend is being perceived on screen.
Speaking on ITV's Daybreak this morning (13 January), Antony insisted that Lee wasn't committing career suicide by entering the CBB house, where he has been seen embroiled in a messy love triangle and pole dancing in a pair of minuscule pants.
However, 32-year-old Antony did admit that he wanted to have a word with his younger bandmate.
"It's not a career suicide, I think people have seen how stressful and intense the Big Brother house is," Antony said. "I've never been in there but I'm sure when he comes out we'll be able to have a chat and I'll be able to say to him 'What you doing?'"
"I would say to him 'Lee Roy come on, wake up!' … As we all know it takes two to tango, it's not just all Lee. Lee's a good lad, I wouldn't be in a band with him for 14 years if he wasn't, so he's got a heart of gold. He's a good lad."
Antony then added that Lee is only just realising that he's coming across badly on TV and joked he's not used to the negativity: "He's never had boos, welcome to my world Lee!"
Since entering the CBB house on 3 January, 30-year-old lothario Lee has been causing quite a stir by kissing fellow housemates Casey Batchelor and Jasmine Waltz and appearing to lead both girls on with his on-off behaviour.
Although he began the competition by getting close to Casey and toying with the idea of a relationship with her, he quickly changed his mind and decided that he fancied Jasmine instead - much to Casey's dismay and confusion.
On top of that, Lee then admitted that he had previously been intimate with a man during a candid chat with Ollie Locke, Luisa Zissman and Jasmine.
Rumours soon began to circulate that the Blue singer had once enjoyed a fling with bisexual bandmate Duncan.
However, Antony was quick to dismiss the speculation today, saying: "No that [story] is all rubbish, it's all fabricated. There was an interview we did about three or four years ago and it was [titled] 'The naughtiest things Blue have done' and [Lee and Duncan] said 'Oh, we did this one day' and then it got blown out of proportion."
Despite the mixed public reaction Lee has received since starring in Celebrity Big Brother, Antony revealed that he wouldn't mind appearing on a series of the popular Channel 5 show too.
"I'd love to do it. I did I'm A Celebrity... Get Me Out Of Here! and I went in there as the guy from Blue and came out as Antony Costa, so a lot of people saw me for who I was," he said.
"I think Lee has gone in there showing what he's about and he's a good lad and hopefully he can come out of it smelling of roses."
Antony is currently expecting his second child and excitedly shared a cute scan picture of his unborn baby last week.
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