Roy Keane's return as the Football Association of Ireland's prodigal son is as much for showbiz and filling Dublin's Aviva Stadium as it is for its "football logic", according to Eamon Dunphy. The Irish football pundit, who helped write the former midfielder's autobiography, said the pairing of Keane with Martin O'Neill "would be like fire and ice" during their reign. Dunphy said that "better men have failed" to control Keane in the game but the duo may work "because they are both proteges of Brian Clough".

"In terms of bringing back the fans, energising the younger players who would have idolised Keane when he was a player and in terms of just fun, it might just work between him and Martin O'Neill, who, by the way, is a very good appointment by the FAI," he said.

News of Keane's possible comeback was met with a mixture of amusement and bewilderment among the Republic's fans north and south of the border. For at least one follower of the Boys in Green it could even provide an entertaining epilogue to a comedy he penned about Keane's infamous clash with Mick McCarthy on the island of Saipan during the 2002 World Cup. Ireland and life-long Bohemians fan Mick Nugent was preparing to address the Irish Constitutional Convention in Dublin on Saturday when he was told about Keane's pairing with Martin O'Neill to manage the national team. Along with the Father Ted writer Arthur Matthews, Nugent co-wrote I, Keano, the hit comic opera that transported the Keane-McCarthy civil war to ancient Rome.

Nugent, an atheist who is campaigning for the abolition of the Republic's Blasphemy Law, said: "I'm going to stand up at the Constitutional Convention and say: 'Here's another good reason why we should get rid of blasphemy – it will allow Roy Keane to say what he likes to the Ireland players without fear of prosecution. It's fun news, of course, and the good old FAI is still the exploding clown car that keeps giving. I suppose we're going to have to amend and tweak I, Keano because no doubt Keane will provide some more plot for us.

"The fall out in Saipan between Keane and McCarthy divided Ireland, it was my generation's Civil War. And now he's back and there could be another one."

Unlike Nugent, the Irish Independent took a less irreverent tone in welcoming the partnership on its back page with the headline: "O'Neill and Keane dream team". Fellow Corkonian Ron Portnoir had a more wry approach to the FAI's prodigal's return. "Roy Keane is the perfect choice, if you are a nihilist," he told The Observer. Ken Murray, who followed the Republic's fortunes under McCarthy when Keane was still playing described the new pairing as "a marriage that will end in tears".

Inside Solitude stadium in Belfast, Cliftonville fans, who, in the main, support the Republic of Ireland, reactions were equally mixed about the Keane appointment. Before Cliftonville's Irish League game with Dungannon Swifts, Brian Courtney from west Belfast welcomed Keane back: "He's hot-headed but so what? Maybe that's what Ireland needs, his encouragement. I would be afraid and motivated if I played for him."

Liam Murray, a Cliftonville fan all his life who supports Manchester City in England, admitted he may not be the most objective commentator on Keane's career. "I don't know whether it will work or not because Keane doesn't back down to anyone. I would be very surprised because they are too very independent men although they do respect each other. The players will be well motivated and there will be no passengers in the squad."

Sitting side by side behind the goal at The Waterworks end of Solitude, Cliftonville fans Eoin Stewart and Gavin Higgins were divided over Keane, like much of the rest of Ireland. "I just don't like the guy. He is ignorant as a player and a manager," said Stewart. But Higgins disagreed: "He's great and is exactly what Ireland needs after Trapattoni."

Back in Dublin Ed O'Loughlin said it will at least galvanise supporters after the failure to qualify for the World Cup in Brazil. "They say O'Neill can deliver a bollocking with the best of them. Imagine having him giving out to you at half time and you look past his shoulder and there's Roy Keane too, staring wordlessly back at you. It'd be like Goldfinger and Oddjob. There'd be no problems with players not tracking back."