FitzGerald and Haughey had three crunch TV battles in the '80s and FitzGerald recalls their "nervewracking" nature. "There was no debate in the 1981 election but I did have three televised debates with Haughey, twice in 1982, and in 1987, " he said. "They were nervewracking, as you never knew how they were going to work out, and even when they were over, I never knew if I had won, lost or drawn."

Five years since Ahern's last televised head-to-head with Michael Noonan, Enda Kenny will come up against the Taoiseach in this week's debate, which will start at 9.30pm on Thursday.

Last time around, much of the media commentary suggested that Noonan had won the debate, but this didn't stop Fianna Fail's landslide victory. So with little separating the sides ahead of polling day on 24 May, Thursday's debate is crucial to both parties.

Looking back over the last 25 years, FitzGerald said: "In the 1987 debate, I completely lost my concentration and I couldn't get it back for a few minutes, so I just kept asking Haughey the same question over and over again.

"I thought I had lost the debate but after it was over everyone thought this was part of my strategy and that I had given a good performance and won the debate.

"In one of the debates, Haughey denied that he had said something, so I produced a piece of paper with his quote on it and after the camera focused in on what was on the paper, that did it for me.

"It is very uncertain how important the debate is to the overall election. I think that by the time the debate comes around, the result is largely decided, but a bad debate can marginally affect the vote."

Asked how he felt this week's debate between Kenny and Ahern would turn out, FitzGerald said:

"I never knew how my own debates went even after I had finished them, so I haven't a clue how this one will go."

Leaders of four of the main parties will also take part in a live debate, chaired by Mark Little, on Prime Time next Wednesday at 9.30pm.

Pat Rabbitte, Labour; Gerry Adams, Sinn Fein; Trevor Sargent, Green Party and Michael McDowell of the Progressive Democrats will participate in the speciallyextended programme on the eve of the Ahern v Kenny showdown.

It has been reported that McDowell and Rabbitte would also engage in a debate as part of TV3's new Polls Apart programme, presented by Matt Cooper and Eddie Hobbs.

However, TV3 could not say if arrangements for that debate had been confirmed when contacted by the Sunday Tribune.