Ireland coach Declan Kidney has included seven uncapped players in his squad to face the Barbarians.
Ireland meet the invitational side at Gloucester's Kingsholm ground on May 29, and will then embark on a three-Test tour to face world champions New Zealand.
Kidney will not be able to call on the services of his Leinster contingent for the non-cap fixture as the province meet the Ospreys in the RaboDirect PRO12 final on May 27.
Second-row Paul O'Connell is also not selected as he continues to recover from a knee injury, but he has not been ruled out of the tour to face the All Blacks and could yet be included when Kidney names his squad for that trip on Monday, after Ulster and Leinster go head to head in Saturday's Heineken Cup final.
Two spots in the 24-man squad have been left open and will be filled next week.
The front-row trio of Munster hooker Mike Sherry, Connacht prop Ronan Loughney and his Ulster counterpart Declan Fitzpatrick are the uncapped players in the pack, while behind the scrum impressive Munster wing Simon Zebo and the Ulster trio of Nevin Spence, Craig Gilroy and Paul Marshall are included.
Kidney has also selected a nucleus of experienced campaigners, with fly-half Ronan O'Gara, lock Donncha O'Callaghan and hooker Rory Best all among the party.
And the coach revealed he has already decided on the majority of the squad to head to New Zealand, although he will be paying particular attention to those involved in this weekend's European showpiece at Twickenham.
He said: "The game against the Barbarians is vital for us in our preparations for the tour as it gives some players the chance to gain match fitness if they have not played for a couple of weeks, allows us to further expose some players to the national set-up and also gives us the opportunity to get some foundations in place for the Test series.
"We have a good majority of our selections decided on for the tour party at this point, but the Heineken Cup final gives us possibly one last opportunity to watch players in what will be a massive occasion for Irish rugby."
Full Ireland squad:
Forwards: R Best (Ulster), T Court (Ulster), S Ferris (Ulster), D Fitzpatrick (Ulster), C Henry (Ulster), R Loughney (Connacht), J Muldoon (Connacht), D O'Callaghan (Munster), P O'Mahony (Munster), D Ryan (Munster), M Sherry (Munster), D Tuohy (Ulster), A.N.Other.
Backs: D Cave (Ulster), K Earls (Munster), C Gilroy (Ulster), P Marshall (Ulster), C Murray (Munster), R O'Gara (Munster), N Spence (Ulster), A Trimble (Ulster), P Wallace (Ulster), S Zebo (Munster), A.N. Other.