The 32-year-old found herself in the sing-off against Rylan Clark after the pair received the fewest amount of public votes. Nicole Scherzinger opted to save Clark, her own act, while Gary Barlow also chose to save mentee Poole.
Tulisa Contostavlos decided to send Clark home, and after seemingly struggling with the decision, Louis Walsh chose not to vote for either act and sent it to Deadlock.
Poole was then announced as the act with the fewest number of public votes.
Following Clark's performance of 'One Night Only' from Dreamgirls and Poole's cover of Faith Hill's 'There You'll Be', the decision went to the judges.
> 'X Factor' Week One Results Show - live blog
Scherzinger said to Poole: "You are a beautiful and effortless singer and I respect your style, but obviously I have to stick with my boy because I do believe in him."
Barlow added: "Thank god you [Carolynne] got to sing like that, because this makes the decision easy for all the judges."
With Tulisa voting to save Carolynne, the final decision rested on Louis Walsh.
After deliberating for some time, Walsh complained that the decision was "so hard". Barlow protested that it was in fact "easy", while Scherzinger said that Rylan provided the "entertainment factor".
Walsh appeared to have saved Carolynne by saying: "I'm going to go with Carolynne, I want to keep Carolynne."
However, when pressed by Dermot O'Leary to confirm his decision, he suddenly changed his mind and declared: "I want to take it to Deadlock."
Gary Barlow - who had been standing up during the final Deadlock announcement - was furious with Walsh's decision, and stormed out of the studio.
Carolynne Poole said to O'Leary after the news was announced: "I'm okay. I'm glad Rylan's got a shot because he's been given a tough time."
Later on The Xtra Factor, Barlow said of Walsh's decision: "Absolute joke. I'm so gutted for [Carolynne], that was the most unbelievable thing. Two years running you've lost out to joke acts.
"Why send it to Deadlock? It's ridiculous. We always try to judge it on the last performance, how can you compare those performances?"
Explaining himself, Walsh later said: "I wanted to see who got the least amount of votes, it's a very tough one."
The X Factor continues next Saturday, October 13 at 8.20pm on ITV1.
What did you make of Louis Walsh's decision to take it to Deadlock? Should Carolynne have left the competition? Let us know in the comments section below.
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