Town have withdrawn keeper Shane Supple and midfielder Owen Garvan from the Republic of Ireland U21 squad playing in the 11th annual Madeira Cup tournament later this month. Striker Billy Clarke and defender Michael Synnott are still included in the Irish travelling party.
The Irish youngsters will play Slovakia on February 27th, a Madeira side a day later and Portugal on March 2nd in a competition they won last year.
Supple and Garvan have been withdrawn as they will be required for the Town games at Southampton on February 24th and at home to QPR on March 3rd.
Givens is treating the tournament as a preparation for UEFA European Championship qualification group games against England, Portugal, Bulgaria and Montenegro played between June 2007 and September 2008. The winners of the 10 groups plus the four best runners-up go through to the finals in Sweden in 2009.
None of the four Town players originally named in the squad have previously won an U21 cap, although Billy Clarke received a call earlier in the season but was withdrawn due to a clash with domestic fixtures.
Republic of Ireland U21s: Rene Gilmartin (Walsall), James Russell (Chelsea), Tony Kane (Blackburn Rovers), Joe O'Cearuill (Brighton and Hove Albion), Conor Powell (Bohemians), Darren O'Dea (Celtic), Stephen O'Halloran (Aston Villa), Ryan O'Leary (Kilmarnock), Michael Synnott (Ipswich Town), James O'Brien (Dunfermline Athletic), Billy Dennehy (Sunderland), James Chambers (Shelbourne), Michael O'Connor (Crewe Alexander), Gary Curran (Sligo Rovers), Ian Morris (Scunthorpe United), John Paul Kelly (Bohemians), Chris McCann (Burnley), Ronan Finn (UCD), Billy Clarke (Ipswich Town), Adam Rooney (Stoke City), Jonathan Hayes (Milton Keynes Dons).