Everton's James McCarthy will miss the Republic of Ireland's four upcoming friendlies with an ankle problem.
The midfielder has dropped out of the 32-man squad, along with Birmingham City goalkeeper Darren Randolph and West Ham United defender Joey O'Brien, who has opted to rest after an injury-plagued season.
Martin O'Neill's side host Turkey at the Aviva Stadium on May 25, before facing England's World Cup opponents Italy at Fulham's Craven Cottage six days later.
The Boys in Green will then travel to America for matches against Costa Rica, another side who await the Three Lions in Brazil, and Portugal, on June 6 and June 10 respectively.
McCarthy, 23, has made 23 Ireland appearances since debuting in 2010.
Full squad:
Goalkeepers: David Forde [Millwall], Rob Elliot [Newcastle].
Defenders: Richard Keogh [Derby], Marc Wilson [Stoke], Seamus Coleman [Everton], John O'Shea [Sunderland], Alex Pearce [Reading], Stephen Kelly [Reading], Damien Delaney [Crystal Palace], Shane Duffy [Everton], Ciaran Clark [Aston Villa], Stephen Ward [Brighton].
Midfielders: Jeff Hendrick [Derby], Glenn Whelan [Stoke], Paul Green [Leeds], Aiden McGeady [Everton], Anthony Pilkington [Norwich], James McClean [Wigan], Stephen Quinn [Hull], David Meyler [Hull], Wes Hoolahan [Norwich].
Forwards: Robbie Keane [LA Galaxy], Shane Long [Hull], Daryl Murphy [Ipswich], Jonathan Walters [Stoke], Kevin Doyle [QPR], Anthony Stokes [Celtic], Simon Cox [Nottingham Forest], Connor Sammon [Derby].
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