Fans may know that Brendan took himself to A&E the morning before last week's Strictly show, after suffering problems with his breathing.
He still performed later that night with Anastacia, but since then, Brendan has now been told by doctors to rest and will be re-assessed on Friday (21 October) to see whether he is able to perform or not.
Brendan revealed he has been temporarily replaced by Gorka while appearing on Strictly: It Takes Two. He said: "I'll let you into a little secret. We have the lovely Gorka stepping in for me for a few days."
He then joked: "I don't know how happy I am about it, he's Spanish, he's good looking and has a body which is pretty much the best on the show... I kind of have the feeling it's going to go downhill for me from here."
A BBC spokesperson, meanwhile, confirmed Brendan is currently on rest to The Mirror. They said: "Brendan has choreographed the routine but is resting until Friday as per doctors orders. So Gorka will be running the routine with Anastasia in training until then."
Gorka had previously danced with EastEnders actress Tameka Empson on Strictly, but they had been the second pair to be eliminated from the show.
Tameka found herself in the bottom two alongside Laura Whitmore and Giovanni Pernice, and following the dance off, the judges voted in favour of Laura to stay.
Following her exit, Tameka said she was "surprised" she had been given the boot, as she didn't think she "put a foot wrong" during her dance. She said: "It felt too soon, I have a lot more to give."
News Gorka could now step in to dance with Anastacia comes after Brendan recently revealed he had been to A&E with a lung infection.
Taking to Twitter, Brendan told fans: "#NHS Doc's, Nurses & staff are phenomenal. Thank you for looking after me in the wee hours. Lung infection now under control so thank you.
"Had to take myself to A&E as I couldn't breath very well so not enough oxogen getting through. Incredible care, cannot thank enough #NHS."
#NHS Doc's, Nurses & staff are phenomenal. Thank you for looking after me in the wee hours. Lung infection now under control so thank you— Brendan Cole (@BrendanCole) October 15, 2016
...had to take myself to A&E as I couldn't breath very well so not enough oxogen getting through. Incredible care, cannot thank enough #NHS— Brendan Cole (@BrendanCole) October 15, 2016
It's not the first time Brendan and Anastacia have had to deal with injury.
Anastacia, a breast cancer survivor, had previously torn the scar tissue from her mastectomy surgery while dancing and that had left her unable to compete in Strictly's very first dance off. She had been in the bottom two alongside Melvin Odoom, but bosses deemed that Anastacia was unable to compete and went straight to a public vote to decide which contestant would leave the competition.
Melvin had received the fewest public voted and became the first celebrity to leave Strictly. Anastacia was given the all clear to dance again a few days. She released a statement on Twitter telling fans that her condition will continue to be "monitored." It also said: "Anastacia is doing this to raise money for breast cancer, so unless a doctor tells her she can't carry on, quitting would never be an option."
Strictly Come Dancing continues Saturday 22 October on BBC One.
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