How has Blake Shelton managed to mentor nearly half of The Voice's winning contestants? Simple: He rigged the voting system, Alicia Keys says in a preview of a forthcoming interview on The Ellen Degeneres Show.

Keys, who mentored eventual third-place finisher We McDonald on Season 11, tells Degeneres that she can't believe Shelton has managed to coach five Voice champs (his most recent, Sundance Head, was crowned Dec. 13). By contrast, Adam Levine has coached three winners, Usher, Pharrell and Christina Aguilera have coached one and Shakira, Gwen Stefani, CeeLo Green and Miley Cyrus have all managed zilch.

"I'm a little pissed off at Blake," Keys says. "I'm just sick of Blake, you know what I mean? Apparently he just thinks he's like Mr. I win-all-of-them and all this. I told him this game must be rigged. Somebody else needs to start winning this game or people are gonna think Blake is over there paying somebody."

Still Keys isn't so worried about Team Adam.

"He was extremely confident, Adam," she explains. "I was like 'I don't care.' I was like, 'Nobody's scared of you.'"

Nobody, Adam.

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