Charles Gray QC, for Botham and his former England team mate Allan Lamb, said: "We say he is not the fair-minded, balanced observer of the cricketing scene he would have you believe, but someone who loses no opportunity to denigrate and humiliate Ian Botham."
Botham and Lamb are suing Imran over an "offensive personal attack" on them in India Today magazine which, they say, called them racist, uneducated and lacking class.
Botham alone is suing Imran over a May 1994 report in the Sun which he alleges accused him of ball-tampering - something he says he has never done.
Imran, who denies libel, says his words were taken out of context and he was only trying to defend himself.
Mr Gray, in his closing speech, told the jury that Imran's defence of qualified privilege fell "at every hurdle".
It failed because the articles by the two former England players, to which Imran responded, were justifiable, and because his "counter-attack" went beyond self-defence. Most of all, Imran was malicious in that the allegations of racism and ball-tampering did not stem from an honest belief, the QC said.
He reminded the jury that Imran was responsible for the way his case was conducted by George Carman QC. Mr Gray asked "what in heaven's name" sensational 12-year-old tabloid allegations about Botham, cocaine and Miss Barbados, introduced by Mr Carman, had to do with the action.
"I'm suggesting to you that that is a plain, old-fashioned smear introduced on the off-chance that one or other of you may be prejudiced as a result of it being made," Mr Gray said.
He asked the jury to consider Imran's review of Botham's autobiography, in which he took "every opportunity to nit-pick" and introduce jibes at his expense.
On the question of damages, he described racism as a "grave libel" whereas ball-tampering amounted to the very serious charge of cheating.
Any award could be aggravated by the absence of an apology and the conduct of the defence over the ball-tampering allegation. He concluded: "This is not a case where my clients want an extravagant award.
"But, in the circumstances, they are entitled to look to you for an award of damages of sufficient size for them to be able to point at it after this case is over as evidence that you, the jury, reject as unfounded these charges made against them."
The hearing continues today.Reuse content