SCRUM-HALF has always been something of a problem position for Ireland.
It is not that the country does not produce decent players in that position; it is more a case of them being thin on the ground and, while Ireland has claim to some of the greatest names in rugby from Mike Gibson, to Willie John McBride, Keith Wood and Brian O'Driscoll, Irish scrum-halves do not figure in those debates.
If you take Lions representation as a barometer, it is instructive to note that Ireland have not had a scrum-half on a Lions tour since Colin Patterson toured South Africa in 1980.
Peter Stringer has been the mainstay at No 9 for the majority of the last 10 years -- justifiably earning a reputation as one of the best passers in the game -- but has never managed to win over the Lions selectors.
While Tomas O'Leary and Eoin Reddan have come through alongside Stringer to give Declan Kidney decent options, it has hardly been a production line of quality scrum-halves. It is the reason why New Zealander Isaac Boss was brought into the fold in the mid-2000s and now finds himself back in the mix for the November Internationals following injury to O'Leary.
Leinster went to Australia to find a No 9 capable of orchestrating their Heineken Cup challenge and were well served by Chris Whitaker, while Ulster recognised the problem by getting the cheque book out -- first for Scotland's Mike Blair and, when that deal fell through, South Africa's Ruan Pienaar.
The upshot is that when a promising young scrum-half comes on the scene, he is subjected to extra scrutiny, which was the case with Duncan Williams seven years ago.
Talk in rugby circles in Cork at the time was that Williams was the "most promising Irish scrum-half in years" and trips to see him play with Christians Brothers College confirmed that there was ability to match the glowing recommendations.
That ability was recognised at Ireland Schools level and a glance through the players in that 2004 squad reveal that it was a vintage crop. Rob Kearney, Jonathan Sexton, Sean Cronin and Devin Toner were all involved in the Schools side and are now in the senior Ireland squad.
Others such as Fionn Carr, Darren Cave, David Pollock and Billy Holland have been clocking up the senior appearances with their respective provinces but Williams, now 24, only got his full contract with Munster this season and has just eight appearances to his name -- all off the bench.
So what happened? Why has the potential that caused such a stir in his schooldays and was subsequently recognised by the Ireland U-21s not been realised at senior level?
Injury has been a major factor. Williams has spent more time on the treatment table than on the pitch since leaving Christians and became something of a forgotten man in Munster rugby.
When he was fit, anyone who took in his All-Ireland performances for Cork Constitution would have seen that Williams' ability was as potent as ever.
As well as injury, O'Leary and Stringer have presented considerable obstacles to progress and Williams struggled to make an impact with Munster, with the third scrum-half slot filled by the likes of Mike Prendergast, Gerry Hurley and Toby Moreland.
Williams made just four senior cameos last season but Munster coach Tony McGahan obviously liked what he saw and the Australian's loyalty was rewarded against London Irish a few weeks ago.
Munster were trailing 23-10 in their opening Heineken Cup pool game when Williams replaced Stringer after 73 minutes. Munster's second-half dominance of territory and possession was not being reflected on the scoreboard and the quest for something tangible was becoming increasingly desperate.
Rather than be overawed by his first Heineken Cup appearance, Williams channelled the urgency expertly, engineering phase after phase and it was his quick tap and go which set up the move that led to Sam Tuitupou's bonus-point-clinching try.
Outside Cork, Williams does not register and when his name crops up, responses generally revolve around his injury problems and not having seen enough of him to give a proper assessment.
In many respects, Williams is somewhere between O'Leary and Stringer. Not as powerful as O'Leary but physical in defence and on the break, not as swift in his passing as Stringer but efficient and accurate and possessed of a keen footballing brain.
Cork Con coach Brian Walsh has worked with Williams for several years and has no doubt that, with his injury problems hopefully behind him, the 24-year-old can become a force in the professional game.
"Definitely," says Walsh. "Duncan has all the skill requirements needed and an excellent attitude.
"I would describe him as a 'hybrid' scrum-half: he is good at a lot things rather than specialising in one area, and his distribution skills, kicking game, defence and game management are excellent.
"If there is one thing that you would pick out about him, it's the difference he makes to the tempo of the game, as you saw against London Irish.
"Duncan invites people onto the ball, might have a probe himself, never panics and tends to take the right options. I believe he was a handy left-back in soccer at one time and those footballing skills are there as well."
While the injury history might cause prospective suitors to pause for thought, Walsh takes the view that coming through that experience has equipped Williams for the pro game.
"He had an awful time of it. He was out for 12 months after a shoulder operation and then for another eight months after he tore his groin/hamstring area, right off the bone. The professional game is all about durability and mental toughness and Duncan has that now having come through those knock-backs.
"I think he is definitely ready to step up to the next level. I suppose you could say that's bad news for us at Con but we like to help players along the way and he's definitely helped us. When you get players as good as Duncan at club level you know it is only a matter of time before they are moving on."
Game-time remains the key issue. Stringer is still going strong (he starts ahead of Williams against Ulster this evening) and O'Leary has only just turned 27.
The international windows should see Williams get some starts for the province and, with more exposure, there is the possibility that English clubs could start sniffing, as happened with Frank Murphy and Eoin Reddan, who were both lured from Munster to the English Premiership after being starved of game-time.
Williams is close to former Munster players Timmy Ryan and Jeremy Manning, both now making their mark at Newcastle, as all three played together with UCC and Con and you would imagine the Falcons have been made aware of Williams' capabilities.
For now, though, it's Munster. Williams may not be a high-profile player but that could change with sufficient game-time and this looks like being a seminal season for him.
His tale of ability, frustration and perseverance is worthy of recognition -- particularly in a position where Irish rugby could use a few good news stories.