The England footballer found herself in the bottom two for the first time after Saturday's public vote, which was extended after the online voting system suffered a technical glitch.
The result saw Scott in the dreaded dance-off, which she lost to Chris Ramsey.
Facing the comedian and professional partner Karen Hauer, Scott and trainer Neil Jones failed to wow the judges with a repeat of their Samba to Sister Act’s Joyful Joyful.
But the result was incredibly close with judges Craig Revel Horwood and Motsi Mabuse voting to save Alex and Neil. However, the couple went home after Bruno Tonioli and head judge Shirley Ballas opted to save Chris and Karen.
When casting the deciding vote, Ballas said: “This is a very, very difficult decision. Both couples danced extremely well and it’s going to go to personal taste.
“I’m going to go with the couple that I felt had the most content and was more powerfully entertaining and therefore I am saving Chris and Karen.”
Speaking to host Tess Daly about her time on the show, Alex said: “I’ve been a fan of Strictly forever so to even be here and dance here every week.
“I’ve literally lived out another dream. I had football and then this chapter. I have to thank my dance partner, he’s incredible.
“Thank you to everyone… Thank you for having me.”
On Saturday night, Strictly's online voting system suffered a technical glitch, leaving many viewers unable to vote. However, the system was subsequently fixed and the voting period extended.
Only four couples are now in the running for the glitterball trophy, with all remaining pairs expected to return to the semi-final next week.
Strictly Come Dancing returns on Saturday