Justin Bieber has felt the backlash of music critics who have branded his performance in New Jersey "sluggish," "bored" and "lazy" and accused him of lip-syncing large portions of the show.

On Wednesday night, the international pop superstar took to the stage at the Prudential Center in Newark as part of his ongoing Believe world tour, but his uninspiring performance prompted criticism from reviewers in the audience.

Mesfin Fekadu of the Associated Press has written a scathing report about Bieber's show, insisting the singer was "not in pop star form," while also accusing him of lip-syncing most of his songs and failing to keep up with his dancers.

He writes, "He seemed to be lip-syncing and his sluggish, lazy dancing didn't match the oomph of the beats... Bieber phoned in a good amount during his show; at some moments, he even appeared bored. He was clocking in - another day, another sold-out concert... When performing the hit Beauty and a Beat, he couldn't keep up with his background dancers.

"He was lip-syncing again... During She Don't Like the Lights, Bieber barely moved to the track's futuristic beat (maybe it was the leather tights?)."

Chris Jordan of local newspaper the Asbury Park Press was also disappointed with the 19 year old singer's performance, insisting the star did not deliver during the few moments of the show when he actually attempted to sing.

He writes, "As for Bieber the performer, well, there's not a whole lot to believe in. His voice is thin and reedy... Unfortunately, his dancing isn't any better than his singing. His turns are loose and his body control is sloppy. He seemed divided as to whether he should join his team of dancers full force or just let them do most of the work."