The news was revealed as the grand finale of the series kicked off on Saturday night.
Judges Alesha Dixon, Amanda Holden and David Walliams joined Simon on stage for the last time this year.
While Ant and Dec returned for their Britain’s Got Talent hosting duties.
Confessing they had “big news” to share, the hosting duo revealed that Sarah would be the eliminated act to be given a second chance on the show.
Britain’s Got Talent: Ant and Dec have revealed the 2017 wild card act [ITV]
Britain’s Got Talent: Simon Cowell’s Golden Buzzer act Sarah Ikumu is back for the final [WENN]
Speaking about the decision to bring back Sarah, Simon explained: “There was only one person we all genuinely thought deserved to be in the final.
“It was the right decision.”
Simon was left “speechless” over the Britain’s Got Talent results earlier this week.
The judge couldn’t hide his shock after Ned Woodman got through and his golden buzzer act Sarah was sent home.
Britain’s Got Talent: Sarah Ikumu was sent home earlier this week [ITV]
Viewers were quick to take to Twitter to comment on the 57-year-old’s reaction over the matter.
One person said: “Simon’s speechless #BGT #BritainsGotTalent.”
A different account put: “Well Simon clearly didn’t expect him to go through .. Don’t think he realised the camera was on him then…! #BGT #bgt2017.”
Another user added: “#BGT well done Ned. Seeing Simon Cowell’s face was a picture. Thought Sarah should of been in final tho.”
Britain’s Got Talent: Simon confessed that all the judges agreed Sarah should be the act to return [ITV]
While a different person commented: “Would love to know what Simon said to Amanda when Ned got put through. He clearly wasn’t pleased #BritainsGotTalent #bgt.”
Britain’s Got Talent will return for another series in 2018.