Monday Hamid Karzai's main challenger Abdullah Abdullah demanded the removal of commissioner of election body before going to runoff vote set for Nov. 7.
"One of the conditions for having fair voting in the second round is sacking Mr. Azizullah Ludin the chief of the so-called Independent Election Commission (IEC)," Abdullah told newsmen at a press conference.
Karzai's former Foreign Minister made these remarks a day after Ludin in talks with The New York Times predicted the chance of victory for the sitting president Karzai in the second round.
Ludin, as Abdullah claimed in the conference, told New York Times that Karzai would sweep the runoff as he won the first round.
In the preliminary result of the fraud-tainted Afghan presidential election held on Aug. 20, Karzai won over 54 percent of nearly six million votes while Abdullah bagged 28 percent, Xinhua reports.
It was also reported, Mr Abdullah made the demand during a news conference when he outlined a list of conditions for a fair second round.
"He has left no credibility for the institution," Mr Abdullah was quoted by the AFP news agency as saying.
"What's the solution? Another commissioner from the same commission should take his position," he said.
Officials involved in flawed polling are being removed ahead of the run-off, the UN has said.
But there are still concerns about the ability of the run-off to avoid mistakes made in the first round, correspondents say.
Campaigning officially began over the weekend but the Taliban threatened to launch a fresh wave of violence and urged people not to vote in what they called an "American process," BBC News reports.
Reuters quoted Abdullah Abdullah as saying, "One of our conditions is the immediate removal of (commission chief Azizullah) Ludin because he has no credibility before the people."
"We will wait for the commission's reply until October 31 and until then we suspend all of our relations with the commission," he told reporters. He refused to say what he would do if this condition were not met, Reuters reports.