Tommy Sheridan has sacked his legal team and will represent himself in his case against the News of the World.
Tommy Sheridan is considering representing himself in court
The Socialist MSP had been represented by Richard Keen QC but the advocate has not been in court since last Friday due to commitments in London.
Junior advocate Graeme Henderson had conducted Mr Sheridan's case.
He is suing the Sunday tabloid in a £200,000 defamation action over a series of articles about his sex life which he claims were "untrue".
The development was triggered by Mr Henderson's cross-examination of Anne Colvin, who claimed she caught the MSP taking part in a threesome in a Glasgow hotel.
The case was prematurely halted on Thursday when the junior advocate put it to the witness that she had previously been sentenced to 18 months for credit card fraud.
Mrs Colvin, 54, denied the allegation and said she had never been convicted of such an offence.
The jurors were sent away while Lord Turnbull attempted to resolve the matter.
Upon their return, he informed them that the suggestion made to Mrs Colvin was a "very serious one".
On Friday, in court, Mr Sheridan revealed it was the catalyst for his decision to sack his legal team.
When the jurors were called into court, the judge handed them over to Mr Henderson to let him explain what had been going on in their absence.
Mr Henderson told the court: "Mr Sheridan has elected to dispense with the services of his counsel and is now about to conduct the case himself.
"That will mean that I am about to disappear from the place where I am sitting and Mr Sheridan will take my place."
Turning to the witness, he said: "Mrs Colvin, yesterday I asked you questions and put to you propositions to the effect that you had been convicted of credit card fraud.
"I had no proper basis for putting those questions and propositions to you."
Mr Henderson said he realised she was a woman of good character and apologised unreservedly for his error.
He then left the court as Mr Sheridan, the former leader of the Scottish Socialist Party, took his place on the front bench.
The Glasgow MSP apologised to the jury, to Mrs Colvin and to the judge for the delay and requested an adjournment until Tuesday to allow him time to prepare his case.
He added: "I have been less than satisfied since Monday in relation to the conduct of my defence and I was incandescent with rage yesterday.
"I have to offer an apology from myself to Mrs Colvin.
"The question was not prompted by myself."
Lord Turnbull granted an adjournment until Tuesday and told the jury it would have been unfair to expect Mr Sheridan to start representing himself this afternoon.