London, Oct 13 - British pop star Robbie Williams left fans scratching their heads after his performance on the reality show "X Factor" recently.

Dailymail. co. uk reports that this performance was supposed to be a comeback after his battle with addiction to prescription drugs. Williams appeared wide-eyed, unblinking and sweating. He also stopped mid-way repeatedly to shake hands with members of the audience and to talk to the crowd. He also seemed out of sorts with his dance moves.

Some fans were critical of Williams' performance on Internet message boards.

"It's totally disgusting that he was allowed to perform in such a state," wrote a fan.

Another fan claimed that the performance was so bizarre that her children were asking her what was wrong.

But some fans defended Williams. "Give him a break, he was just nervous. You can see how overwhelmed he was with the crowd and loved being back on stage doing what he does best," wrote a fan. (IANS)