The inclusion of so many under-21s, including recent debutant Aaron Connolly, Parrott, Liverpool goalkeeper Caoimhin Kelleher, Stoke City defender Nathan Collins, and Southampton attacker Michael Obafemi, comes as McCarthy prepares for a friendly against New Zealand (Thursday, November 14), before turning to the "tried and the trusted" for the crucial Denmark game the following Monday.

Injury-victims Brady, who has missed Ireland's last four games, and David McGoldrick are back in McCarthy's extended squad, with the final list set to be named early next week. Out-of-favour Southampton striker Shane Long retains some chance of a first appearance in over a year as he also makes the provisional cut.

Darren Randolph is included in the squad as he recovers from a thigh strain, although Sheffield Wednesday’s Keiren Westwood and Kelleher are recalled to compete for the position.

“Darren is hopeful that he will be fit for Denmark and he has time on his side,” McCarthy told FAI.ie, although he will scout his rivals for the number one jersey.

“We have to plan for all eventualities however. There is a chance that Caoimhin could play for Liverpool against Arsenal in the Carabao Cup on Wednesday while Keiren got back into the Wednesday team against Leeds last weekend and we will watch him against Blackburn this Saturday.”

Defenders Ciaran Clark and Darragh Lenihan, who missed the October games with a knee injury, are pushing to feature in a final squad for the first time under McCarthy, as well as Crystal Palace midfielder James McCarthy.

“The New Zealand game is a chance to have a look at the players who are fighting to be in the team and some of the players fighting to be in the squad. We saw how beneficial it was to change things up for the recent Bulgaria friendly and we may well do that again against New Zealand,” said McCarthy.

“It could be the perfect opportunity to have a look at Troy Parrott for example and see how he makes the step-up to senior international football after impressing so many people at underage level with Ireland and Spurs.

“We know what we have to do against Denmark and we will look to the tried and the trusted to win that game but who knows what will happen against New Zealand. Maybe someone will take their chance in that match and give me something to think about.”

Provisional Ireland squad v New Zealand and Denmark

Goalkeepers: Darren Randolph (Middlesbrough), Mark Travers (AFC Bournemouth), Kieran O’Hara (Burton Albion, on loan from Manchester United), Keiren Westwood (Sheffield Wednesday), Caoimhin Kelleher (Liverpool).

Defenders: Matt Doherty (Wolves), Cyrus Christie (Fulham), John Egan (Sheffield United), Shane Duffy (Brighton & Hove Albion), Kevin Long (Burnley), Enda Stevens (Sheffield United), Darragh Lenihan (Blackburn Rovers), Ciaran Clark (Newcastle United), Derrick Williams (Blackburn Rovers), Ryan Manning (QPR), Nathan Collins (Stoke City).

Midfielders: Callum O’Dowda (Bristol City), Conor Hourihane (Aston Villa), Josh Cullen (Charlton Athletic, on loan from West Ham United), Glenn Whelan (Hearts), Alan Browne (Preston North End), Robbie Brady (Burnley), James McClean (Stoke City), Jeff Hendrick (Burnley), James McCarthy (Crystal Palace), Alan Judge (Ipswich Town), Jack Byrne (Shamrock Rovers).

Forwards: Aaron Connolly (Brighton & Hove Albion), David McGoldrick (Sheffield United), James Collins (Luton Town), Sean Maguire (Preston North End), Callum Robinson (Sheffield United), Aidan O’Brien (Millwall), Kieran Sadlier (Doncaster Rovers), Ronan Curtis (Portsmouth), Shane Long (Southampton), Michael Obafemi (Southampton), Troy Parrott (Tottenham Hotspur), Scott Hogan (Stoke City, on loan from Aston Villa).