Diarmuid O'Sullivan will never hurl again for club or county, the Sunday Independent can reveal. To followers of Cork hurling, that may not be a big surprise, but his reason for making the decision will come as a shock to all. "At 30 years of age, a man should be able to make up his own mind whether or not he should have to wear a helmet."

A new rule making the wearing of a helmet compulsory comes into force next January, and this, remarkably, is the final straw for the former Cork full-back.

O'Sullivan played his last game for the Rebels in the All-Ireland semi-final defeat to Kilkenny last August and although an inter-county return appeared on the cards, the man known as 'The Rock' is putting his hurl down for good and embarking on a new sporting career with Highfield rugby club.

O'Sullivan's club, Cloyne, have been knocked out of the local championship and he is ready now to try something different, and helmet-free. "I've been very lucky with the lads in Highfield, they have been very good to me," says O'Sullivan. "We're in off-season at the moment but pre-season starts soon and I'm really looking forward to it."

Walking away from the game that made him a household name -- and from the team he soldiered with for so long with -- has not been easy for O'Sullivan, who admits he spoke to Cork manager Denis Walsh about a shock return to the panel.

"I sat down with Denis and we had a chat about the season ahead," he says. "After the game against Kilkenny last year, I didn't feel I could play again in the full-back line. I told him this and I asked him if I could play a role somewhere else on the field and he said he would think about it. Which he did and he was honest and said he didn't think there was.

"I sat back after the meeting with him and thought for a while, wondering if I would go back and give it a go in the full-back line. I took a few hours to think about it but I had made up my mind after the Kilkenny game that full-back was no more for me so I just had to stick by it."

O'Sullivan felt he still had something to offer Cork further forward and when he scored 3-5 for Cloyne in a championship match against St Finbarr's, others in the county felt likewise. But it wasn't to be. Soon, too, Cloyne's year was over.

"The last couple of weeks have been hard since we lost the club championship. Time is hard to fill, days are hard to fill, but I'll get there. The hardest thing for me since I gave up is that I used to be in contact with the lads all the time. We used to be great buddies but because of the decision I took I knew I had to distance myself from the them. Breaking away from the group and making a conscious decision that you are not part of this group anymore has been the hardest thing."

Of course, he had been through a lot with that group, on and off the field, and the latest posturing between the GPA and the GAA, which could well lead to another strike, does not surprise him. They appear now to be heading down a road all too familiar to O'Sullivan.

"I've been through three of them [strikes], sure I'm well used to it but I think this GPA 'strike' has been brewing for a while, even through in Nickey Brennan's time recognition was coming and coming, then Christy Cooney took over and it was being sorted and sorted and it just never has."

Now that he's removed from the inter-county scene, O'Sullivan says he has had time to really take in how much players put into the game, and this has reinforced his view that the GPA are doing the right thing. "I've always been a supporter of the GPA. I've always backed everything they have done. I think players have to have an official recognised body and they are not going to give up at this stage. Since it started back in 1998, it's just got stronger and stronger. The players need someone to represent them.

"Something is going to have to be done. I weighed up the options when I was thinking about retiring and I saw that nearly 26 hours a week would be spent training and if players can't get something back out of that . . .

"You can see all the money that's been pulled in, even the €19 million they made from the rugby and the soccer over the last couple of years.

"It's fine if you could see it being put in elsewhere but it's very hard for players at the moment to justify what they are doing."

As the economy crumbles in Ireland, the amateurs who play for their counties are feeling the pressure and O'Sullivan feels the GAA need to step up to the plate before it's too late. "There are a lot of lads unemployed, inter-county players who week in week out keep training, doing the best for their county. I think the GAA are going to have to act sooner rather than later.

"At the end of the day, I would ask the question: why are people going to watch matches? It's like going to Thomond Park or Old Trafford -- you're going to see the players or if you pay to go to a concert you are going to see someone perform."

O'Sullivan is sure there will come a time when players will have to get a set match fee and proper expenses. Being involved in the GAA for over a decade allows him the liberty of viewing the association without the rose-tinted glasses most spectators wear. He knows what it's like to put yourself on the line, to deal with highs and lows and to feel pressure. He also knows that it is something players won't put up with forever.

"I think without a doubt the strike could end up with players not playing. I've been to enough meetings throughout the years to know that and I think they are so well organised and structured at this stage it will come eventually. I think the GAA are taking a huge chance by pushing the lads as far as they are because at previous meetings I've been at it's only been the toss of a coin whether the lads would go on strike or not. If the GAA are going to keep pushing and pushing, there is only so much rope you can give a person and I think the lads are at the end of the rope at this stage."

O'Sullivan knows more than most the difficulties that standing up for something you believe in can cause. The most recent dispute between the hurling squad and the county board pitted O'Sullivan and his brother Paudie against their father, Jerry, the current board chairman.

"It was very difficult with my dad being in the position he is in but he understands what I believe in and I understand what he believes in," says O'Sullivan. "But apart from one interview with a certain outspoken man who got in trouble with his mouth a few times, it wasn't dragged into the media. To be honest, we didn't speak about it much. We had small conversations about it but never to a large extent. Neither of the two of us wanted to get in to a discussion about the rights and the wrongs of it so we just didn't.

"And there were rights and wrongs on both sides. Maybe if the time came around again certain people may have conducted their business differently and done things differently in certain aspects. But it's gone and it's done and what was said was said."

People have moved on now, and so has O'Sullivan, who has started coaching in Cloyne, with the U16s. His career was as colourful as it was successful, so much so that he is credited with being the cause of two rule changes in the GAA: the blood sub rule and the infamous interference with the helmet rule.

"It happened with Martin Comerford of Kilkenny," he laughs. "It was something Donal O'Grady mentioned to me. He told me Comerford is a good player but it takes only the slightest thing to put him off. He asked me to try and think of something you could do to put him off.

"I remember the very first high ball coming in and I could see the big long strap sticking out of his helmet. It was made for me so I just pulled it and he didn't know what was after happening, he was just scratching himself, he thought he was after getting a bite or some thing so I kept doing it and doing it, it was very funny. The next time we met Kilkenny they had all their helmets strapped up with tape, it was priceless."

Priceless indeed. Hurling's loss will be rugby's gain.