Taylor Swift joins 'The Voice' as sole Knockout Rounds mentor

Grammy Award-winning recording star Taylor Swift is to serve as the sole mentor for all of the competing artists on each of the four teams on this season of The Voice, NBC announced.
"Swift advised each of the performers during the upcoming Knockout Rounds -- airing Oct. 27-28, and Nov. 3 -- on vocal technique, stage presence and the importance of tailoring songs to fit their personalities and strengths," the network said in a news release Friday. "These artists will continue to try and earn the support of their respective coaches, who will be forced to decide who will move on to the live Playoff Round. Each coach will have the opportunity to strategically steal one more artist in the Knockout Round."
Swift, 24, is to release her fifth album 1989 on Oct. 27. It has already produced the No. 1 single "Shake It Off."
The four teams on Season 7 of The Voice are led by Adam Levine, Blake Shelton, Pharrell Williams and Gwen Stefani. The singing competition is hosted by Carson Daly.