Former X Factor stars Nicole Scherzinger and James Arthur have been unveiled as guest mentors on rival show The Voice UK.
Years and Years star Olly Alexander and singer Anne-Marie will also appear in the ITV singing show to lend a hand to its coaches and each of their remaining six acts.
Each mentor accompanies the coaches during piano rehearsals, offering guidance to each act before they take to the stage in the Knockouts.
Of the six acts that have graduated to each team, only two can progress to the live semi-final of the series.
Scherzinger, who appeared as a judge on The X Factor from 2012-2013 and 2016-2017, joins forces with Will.i.am as she helps coach his team towards the next stage of the competition.
The former Pussycat Dolls star said: “Mentoring young talent has always been my passion and I’m so excited to join this season of The Voice UK as a guest mentor.
“Will is an exceptional coach and has incredible musical ears, and I was so pleased he asked me to lend my support to nurture these artists throughout this process. He has chosen an amazing team and I can’t wait to see where their journeys take them.”
Will.i.am praised Scherzinger for having “so much information and perspective” in the music industry in helping his acts.
Arthur, who won The X Factor in 2012, accompanies Sir Tom Jones, and he said it was “great working alongside the legend” himself.
Sir Tom said of Arthur’s input with his acts: “James was great. We saw eye to eye or ear to ear, if you like, on what we were hearing!
“He always had an opinion but nine times out of ten it was the same as mine and confirmed my thoughts, so we had a very like-minded approach. It was great working with him.”
Alexander, the lead singer in synth-pop band Years and Years, joins Jennifer Hudson, and 2002 singer Anne-Marie helps Olly Murs and his singers.
The Voice UK continues with the Battles stage coming to a conclusion this Saturday (March 9), with the Knockouts starting on Saturday March 16.