Darren O'Dea is ready to step into Richard Dunne's boots on Saturday, but does not expect to be doing so when the UEFA EURO 2012 finals come around. The 25-year-old Celtic defender, who spent last season in the npower Championship on loan at Leeds, has 13 senior caps to his name and perhaps most notably, was part of the rearguard which somehow managed to lay the foundation for a 0-0 qualifier draw in Russia last September. He is also currently something of a rarity at the Republic's Malahide training base, a fit centre-half. Giovanni Trapattoni today added Paul McShane to his 23-man squad after seeing Sean St Ledger join Richard Dunne and John O'Shea on the injury list, and with all three doubtful for Saturday's friendly against Bosnia, O'Dea seems certain to start. However, while he will use the opportunity to once again show Trapattoni what he can do, he is convinced he will not find himself in the same position on 10 June when the Irish open their campaign against Croatia in Poznan. O'Dea said: "If I go in on Saturday and Dunney is not quite fit, I think Dunney has probably earned his place in the Euros no matter how well I do. If I go in, it will be a chance to impress and enhance my reputation with the manager, but certainly think if Dunney is fit, he will play. "I will be ready either way. I hope everyone is fit because that will give us the best possible chance. But if I get in, that will be a massive occasion for me and something I would really look forward to and thrive on. But I hope everyone is fit." Dunne and St Ledger have been Trapattoni's preferred central defensive partnership for much of the past two campaigns, and there seems to be little prospect of him abandoning that should both, as expected, regain full fitness before the business end of the summer gets underway. In the circumstances, all O'Dea can do is remind the 73-year-old Italian that he can be relied upon if needed, and that is exactly what he plans to do. He said: "The times you go in, you need to just show you can be relied on and trusted. That's the main thing. "As a winger or a centre-forward, you can maybe come on for ten minutes and affect the game. As a centre-half, you just need to be reliable, and I think I have done that before, so hopefully if I do get another chance, I can do it again." In any case, O'Dea and those members of the squad who would be considered as the back-up to Trapattoni's starters, the manager relied largely upon the same small pool of players during qualification, have to prepare just as thoroughly as their more illustrious colleagues because they know they could be needed at any time. The defender said: "Yes, absolutely. Everyone in the squad will do that, and that bodes well for us. If everyone is ready to play, then I am sure most will play a part at some stage." Given another worry That readiness to step in could apply to several members of the squad this weekend with injuries casing a real headache for Trapattoni. Assistant manager Marco Tardelli has effectively ruled Dunne and O'Shea out of the Bosnia game with abdominal and ankle problems respectively, while St Ledger too has a groin strain. Perhaps more worryingly, keeper Shay Given will fly to London tomorrow to see a knee specialist over the injury which has prevented him from training for the past two days. The Ireland camp insist the visit is precautionary and that, like Dunne, O'Shea and St Ledger, he remains very firmly part of the squad for the EUROs. A Football Association of Ireland spokesman said: "Shay Given will travel to London tomorrow to visit a knee specialist that he has seen in the past. He will return to Portmarnock in the evening. This is purely precautionary and Shay remains fine for the Euros." Despite the concern over injuries, spirits remain high in the camp in the run-up to the game and Sunday's departure for their pre-tournament training camp in Montecatini, Italy. O'Dea said: "Our squad has got a good spirit about it. Everyone is fighting for places, but it's a healthy competition. We are all enjoying just being here at the minute. Once we get out to Italy, the real work will start."