Back in the November Internationals of 2002, O'Sullivan put what he believed to be his best 15 on the field for the games against Australia and Argentina (the Fiji fixture was used, for the only time in the O'Sullivan era, purely for experimentation purposes), but there was to be a fair few changes to the coach's starting team by the time the World Cup came around the following year.

The backline that took the field for Ireland's November 2002 opener against Australia, and the game against Argentina, had a nice balanced look to it. Girvan Dempsey was enjoying favour over Geordan Murphy at fullback, Shane Horgan and Denis Hickie were the undoubted first-choice wingers, Kevin Maggs and Brian O'Driscoll were the complimentary pairing at centre, while Ronan O'Gara and Peter Stringer were the coach's first choice half-backs.

Eleven months later, though, for Ireland's World Cup opener against Romania in Gosford, things had changed.

While Dempsey was the undisputed full-back in November, Geordan Murphy had made the number 15 shirt his own over the course of the Six Nations.

It was a change of preference that we don't see too often from the Irish coach, but as we all know Murphy missed out on making his mark at the World Cup because of a horrific injury suffered in a World Cup warm-up game against Scotland.

That allowed Dempsey to start the World Cup at 15, and finish it there. That was the change that never happened.

The one that did was highly significant.

Since Ronan O'Gara made his Irish debut against Scotland in the spring of 2001, himself and David Humphreys had played out a riveting tetea-tete for the Irish out-half slot. In November 2002 O'Gara was O'Sullivan's clear preference, and his flawless kicking performance against the Aussies in truly awful conditions only served to emphasise that. O'Gara looked a certainty to start the World Cup as number one out-half back then, but an ankle injury picked up playing for Munster left the Cork man on the sidelines for the start of the Six Nations and allowed David Humphreys to reassert his credentials. By the time October 2003 came about, the Ulsterman was O'Sullivan's first choice.

Up front, there was also some re-thinking done.

Against Australia, the front row comprised Marcus Horan, Shane Byrne and John Hayes, but there was little doubt in anybody's mind that both the loose-head and the hooker were simply keeping the shirts warmed for the injured Reggie Corrigan, who returned against Argentina, and the crocked Keith Wood, who didn't reappear in an Ireland shirt until the World Cup warm-up game against Wales.

In the second row, Gary Longwell and Malcolm O'Kelly were Ireland's first choice, while Victor Costello at six, Keith Gleeson on the open side and Anthony Foley at eight, were O'Sullivan's favoured back-row combination.

By the time the World Cup came around, Corrigan and Wood were firmly installed in the front row, but Paul O'Connell had worked his way into a starting spot in the second row ahead of Gary Longwell, who didn't even make O'Sullivan's travelling party.

By the time the crunch encounter against Argentina came around, Costello had replaced the injured Foley at number eight and both Simon Easterby and Alan Quinlan had taken the number six and seven shirts.

The lesson, then? What's in O'Sullivan's mind today may not necessarily be there come September 2007. Players go in and out of form, injuries occur and the coach may even decide that the style of play he prefers today, and the combinations that make it happen, has gone out of fashion by the time the World Cup rolls around.

Those around the fringes still have more than a fighting chance of starting in Bordeaux.