Manager Martin O’Neill refused to speculate on the possibility of the player featuring as McCarthy attempts to put a hamstring injury behind him. “I really wouldn't know at this moment,” said O’Neill of his chances. “We're really day by day.”

McCarthy clearly struggled with the injury during Everton’s Premier League game with Sunderland at the weekend, but was nonetheless given the green light to travel to Dublin by the Liverpool club’s medical team.

Glenn Whelan, by way of contrast, has made a miraculous recovery from a fractured leg suffered just four weeks ago having taken part in an extensive training session with his club Stoke City on Monday and a lighter runout with Ireland 24 hours later.

Whelan wasn’t even included in O’Neill’s extended squad a few weeks back given the nature of his injury and that appeared to still be the case when he played no part for his club against Tottenham Hotspur at the weekend.

However, Whelan took the initiative by contacting the FAI after his positive session with Stoke and O’Neill thus added him to the squad.

Burnley’s Stephen Ward is still carrying the knock he took when playing for Ireland last month in Germany, but the left-back arrived in camp having played for Burnley and O’Neill described as precautionary the decision to relieve him of training duties.

The week’s first training session also revealed a first glimpse of new boys, Cyrus Christie of Derby County and David McGoldrick of Ipswich Town, the pair having been called up the squad for the first time.