Hoping for Trap's call
DOB: April 22, 1989.
Previous Clubs: Institute, Derry City.
Background: From the Creggan area of Derry, he moved from Institute to Derry City as a teenager, although he almost ended up at Lincoln after the Candystripes' demotion from the top flight. When senior football in Derry was saved, McClean was home within a week to graft his way up from the League of Ireland First Division to the English Premier League.
After a handful of underage appearances for Northern Ireland, he changed allegiance and confirmed his desire to play for the Republic.
Why was he called up? Trapattoni initially left him out of the squad, saying he was sticking with the lads who took Ireland to Euro 2012. In the space of 10 days, he changed his mind, and decided to have a closer look at a player who has turned heads since Martin O'Neill promoted him into the Sunderland starting XI.
Can he go to Poland? It's still an outside bet, but Marco Tardelli yesterday hinted that he could be a man for 'the present' if circumstances change.
Who stands in his way? Damien Duff, Aiden McGeady and Stephen Hunt are three wingers who will be on the plane barring injury.
McClean can operate on both flanks, so his arrival could pose a problem for Seamus Coleman. Trapattoni could hypothetically bring an extra wide man, and leave a central midfielder or a defender behind.
Testimonial: Stephen Kenny (ex-Derry manager)
"He should fit seamlessly into the way Ireland play. He is so adaptable, and can play literally in any position.
"He plays left wing because he's left-footed and quick, but he can play up front, he can play left-back, midfield, and he likes it on the right. He always told me that on the right was his favourite position."
DOB: January 1, 1992.
Previous Clubs: Burnley (loan), Scunthorpe (loan).
Background: Grew up in the Galliagh area of Derry, although his family hail from Donegal.
Represented Northern Ireland up to U-21 level, and sat on the bench as a teenager for a senior friendly in Italy, but switched allegiance to Ireland in 2010. He almost died in a training match when Giovanni Trapattoni called him up in that summer, but has fought back from that serious liver injury.
Why was he called up? Richard Dunne's (above) unavailability opened the door for this game, and Duffy has skipped ahead of Paul McShane in the queue after an injury crisis at Everton allowed him to make an impressive Premier League breakthrough.
Can he go to Poland? Realistically, Duffy probably needs someone else to suffer injury misfortune unless he can do something dramatic this week.
Who stands in his way? Dunne, Sean St Ledger and Darren O'Dea are the three recognised centre-backs, and John O'Shea and Stephen Kelly can cover there too.
Testimonial: Noel King (Ireland U-21 manager)
"Shane is a big boy, he is very talented in the air. He has a lovely strike of the ball, and he has a great desire to be a Premier League player. He has a lot of things going for him. I have no doubt he will make a career for himself.
"How high he goes is up to himself and up to the breaks he gets."