Jack Grealish and Declan Rice would still be playing for the Republic of Ireland but for weak relationships between former manager Martin O'Neill and underage coaches, according to Stephen Kenny.
The current Ireland U21 manager, who will take over from Mick McCarthy as senior manager after the Euro 2020 campaign, has criticised the failure to integrate the best young players, including those of dual nationality, into the senior squad much earlier.
Grealish and Rice, who both represented Ireland at various levels, decided to turn down the green jersey during O'Neill's time in charge.
Martin O'Neill and Declan Rice in 2018.
"I know this is subjective and slightly controversial but if there was a better relationship at the time between under-15, 16, 17, 18, 19, and senior managers, you would feel that both Jack Grealish and Declan Rice would definitely be playing for Ireland now because they would have been fast-tracked earlier and into the first-team," Kenny told Eamon Dunphy on The Stand podcast.
"Jack Grealish played GAA for Warwickshire all the way up in England. He did feel a sense of Irishness.
"[We should have integrated them] much earlier. Jack Grealish is an outstanding player, you wouldn't have had to be a genius to work that out.
Jack Grealish in 2014.
"It needs a coordinated approach between all of the managers. We must be one unit rather than a series of individuals.
"To be fair to Mick McCarthy, we meet once a month with all the managers and he's in contact with myself, Tom Mohan, Colin O'Brien, Andy Reid, Paul Osam, and Jason O'Donoghue, and with Ruud Dokter, the technical director."
Kenny is open to allowing players to play for Ireland through the grandparent rule, but only if "it's very important in their life that they play for Ireland".
He said:
I don't agree with trying to convince people they are Irish or going on bended knee to convince someone. I wouldn't be interested in that at all and we don't need that.
"We need people who it means everything to them to play for Ireland.
"I understand that there is the concept of dual nationality and that can be quite complex - people feel English and Irish or Nigerian and Irish or whatever it is. We can't be naive, it's not always black or white."
Stephen Kenny and his U21 squad.
His belief that the most gifted players should be promoted to higher levels of international football earlier was shown in his U21 squad for the Toulon Tournament. He included five U19 players and two U17 players, although the latter duo, Troy Parrott and Gavin Bazunu, had to pull out through injury.
"That's a policy we must embrace at all the age groups, get the best young players up the ages quicker, and expose them to top international football earlier.
"The emphasis should be on technical ability rather than physical strength."
