The programme pulled in the lowly figure on April 29 for an episode which had Chris Addison, Rufus Hound and Lauren Laverne as guest panellists. The instalment aired in the comedy game's usual 10pm timeslot on Channel 4.
Writing in his Daily Mail diary, Morgan commented: "This is one of the worst ratings anyone can ever remember for any television show broadcast on a major channel at that time.
"Not that this will stop him winning a hatful of more awards at my expense. Britain's Got Talent, which he beat to an RTS award recently, is limping along with just ten million viewers at the moment.
"Ironically, the title of Mr Brooker's show was You Have Been Watching. Altogether now... 'Oh No We Haven't!'"
Morgan also said that Brooker is his "most regular and ferocious TV critic" following a number of jibes about him which have appeared in the star's Guardian column.