SUNDERLAND'S James McClean is set for a key role at Euro 2012 after an encouraging full debut for the Republic of Ireland.

Giovanni Trapattoni has hinted he will be naming Damien Duff and Aiden McGeady in his starting line-up when Ireland open their EuropeanChampionships against Croatia on June 10.

But 90 energetic minutes from McClean in Saturday's 1-0 warm-up win over Bosnia-Herzegovina has given the Ireland boss the encouragement to use him prominently, even if that means emerging as an impact substitute.

"I liked McClean in the first-half and that is why I started him," said Trapattoni. "It was not his first game with new team-mates but it was not easy for him."

While McClean impressed in the first half on the left, the man he effectively replaced in the starting line-up was introduced at half-time and he turned in a man of the match display.

McGeady, though, thinks the emergence of McClean provides Trapattoni with extra options ahead of facing Croatia, Italy and Spain.

The Celtic winger said: "It bodes well for the future. There are players pushing for a starting place and the competition we have in the squad bodes well for the next qualifying campaign for the World Cup after Poland."

But there remains concern over the fitness of Sunderland defender John O'Shea.

Trapattoni has spoken about the need to have "100 per cent fit" players with him at Euro 2012 before indicating O'Shea will not face Hungary on June 4 because of the ankle problem sustained in Sunderland's defeat to Manchester United on the final day.