Former NSW premier Barry O’Farrell says sidelined NSW police minister Mike Gallacher referred to him by several names before the 2011 state election.

But the identity of the `big man’, who’s been at the centre of the latest Independent Commission Against Corruption (ICAC) inquiry, remains a mystery.

“I don’t know who the `big man’ is,” Mr O’Farrell told the ICAC on Tuesday.

“What I do know is that in any meetings with Mr Gallacher he either called me `Barry’, he either called me `boss’ in that curious police jargon … or if someone else was present, he would call me `premier’.”

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The `big man’ shot to prominence after a December 2010 text message from disgraced Newcastle MP Tim Owen’s campaign manager to Mr Gallacher asking “How’s our Big Man going with the $120k”, was tendered at ICAC.

Mr Gallacher and fellow relegated Liberal and former cabinet minister Chris Hartcher both told the ICAC Mr O’Farrell was called the ‘big man’.

The inquiry has heard differing versions about who the `big man’ is, with some saying it was coal magnate Nathan Tinkler while others have suggested it was Mr O’Farrell.

“I don’t know what Mr Gallacher’s mind was but I can’t possibly know what other people call me,” Mr O’Farrell said.