Louis Walsh's hopeful found himself in the bottom two alongside Treyc Cohen after failing to impress viewers with his performance of 'Zoom' by Fat Larry's Band on last night's show.
Adeleye then did battle against Cohen in a final showdown, where he appeared to struggle with his chosen survival song, 'Because Of You' by Kelly Clarkson.
Following the performances, Walsh argued that Adeleye could "grow and grow" through the competition before backing his own act and voting out Treyc Cohen.
Danni Minogue was less sure of her decision, first praising Adeleye for "know[ing] what kind of artist you are", before accepting that Cohen gave a better performance of her survival song, 'One Night Only' by Jennifer Hudson, and voting to keep her safe.
Cole also stuck by her own act, voting out Adeleye while commenting that he didn't deserve to be in the bottom two.
With the deciding vote, Cowell stated that Adeleye had failed to live up to his initial promise and suggested that he hadn't "been looked after properly" by his mentor, finally giving his support to Cohen on the strength of her sing-off performance.
His fate decided, Adeleye told O'Leary that he would get busy writing his own material, while Walsh urged for somebody to offer his former act a record deal.
The X Factor continues next Saturday at 8pm on ITV1.