NEW YORK (December 8, 2012)—Teen sensation Justin Bieber jokingly threatened to trim the long locks of his guitar player during his performance at Z100's annual Jingle Ball Friday night at Madison Square Garden.

Bieber asked the crowd for its opinion of the musician's hair before getting back to the business of entertaining the mainly teen crowd, which shrieked throughout his show.

He also teased the audience with mistletoe, but offered no kisses, just a Christmas song.

Bieber was the final act in a night that also featured performances from Taylor Swift, One Direction, Ne-Yo and The Wanted, who made a little girl's night by bringing her onstage during "Glad You Came."