Five players who can stake a claim for World Cup place against Wales
Cardiff clash last chance for lesser lights to stake claim ahead of next week’s cull
Almost one in five of the players who took part in training at Carton House yesterday won't be there this time next week.
That was the most chilling message from Joe Schmidt to his squad at his first pre-World Cup press conference yesterday as he laid down the gauntlet for those hoping to make the cut.
By August 31, Schmidt will have selected the 31 players who will go to England and Wales, but next week seven or eight will be told to return to their provinces and prepare for the Guinness Pro12 rather than the biggest show in town.
With the core of his front-liners rested this week and unlikely to make an appearance until the Wales return game in three weeks' time, this week and next are the time to deliver for anyone on the fringes hoping to make a charge.
Schmidt confirmed that he is likely to split the squad into 17 forwards and 14 backs - and the expectation is that he will have eight front-rows and at least five half-backs in that number, which squeezes the other positions.
Ireland have only three games before the final squad is named and Schmidt yesterday confirmed that not everyone will get a chance to deliver on the pitch, so those selected for tomorrow's Millennium Stadium clash with Wales can count themselves fortunate to have the chance.
Now they have to take it.
So, who in particular is in need of a big display in Cardiff when Ireland take on Warren Gatland's men?
The Munster man is handed the No 7 jersey, but he must be conscious of the presence of Chris Henry on the bench as he attempts to win Schmidt's trust.
With the first-choice back-row established and Iain Henderson and Jordi Murphy likely to make the plane, the contest appears between those two opensides for the final slot, and Henry is favourite after his rollicking return from injury.
O'Donnell needs a big showing.
The Tipperary lock's ability has never been questioned but there are fears his foot might let him down.
Last capped in 2013, the presence of a fully fit Ryan would be a massive boost to Ireland's chances, with his leadership and experience putting pressure on Devin Toner for the right to partner Paul O'Connell in big games.
However, he needs to prove he can still do it at Test level after a long absence from the arena.
The man who swept the boards at the 2014 player of the year ceremonies must hit the ground running on his return to action.
He hasn't played since October and, with places in the back three at a premium, he must hope that he can deliver from the off in Cardiff if he is to make it back there to face Canada on September 19.
Trimble lacks the versatility others can offer, even if he has delivered for Schmidt before.
Chosen ahead of Gordon D'Arcy and Noel Reid, the feeling is that this is Cave's one shot.
That it comes out of position doesn't help, but the Ulster centre did remain in the panel when D'Arcy was cut during the Six Nations and his ability to work in tandem with Keith Earls will be worth watching.
The 28-year-old offers an ability to cover both centre positions, but must shine in the No 12 shirt to earn Schmidt's approval.
A shaky performance for the Wolfhounds saw the Connacht tyro slip out of the Six Nations reckoning and, with Isaac Boss still to come into the equation and Conor Murray and Eoin Reddan firmly established as first and second choice, he needs a performance off the bench.
A potential game-changer with plenty to work on, Marmion has yet to deliver in his brief appearances for the national team and must show something in Cardiff.