Gareth Southgate has expressed his concerns about the lack of first-team football being played by the members of his latest England Under-21 squad.
Tottenham regulars Dele Alli and Eric Dier have both been included in Roy Hodgson's senior squad, meaning Southgate's highest-profile figures for the European Championships qualifier against Bosnia-Herzegovina and Switzerland - Southampton's James Ward-Prowse, Arsenal's Calum Chambers and Chelsea's Ruben Loftus-Cheek - are little more than squad players at their clubs.
Norwich's Nathan Redmond is the most experienced player at under-21 level with 25 caps and a Premier League regular but beyond him, 24-cap Nathaniel Chalobah has scarcely featured for Napoli, 16-cap Ward-Prowse, the captain, is in and out of Southampton's first team and 12-cap Jake Forster-Caskey rarely starts for Championship side Brighton.
Everton's Brendan Galloway and Liverpool's Jordon Ibe are the only other players in the present squad expected to play anything like regular Premier League football.
Southgate - who revealed he will likely give debuts to Galloway and team-mate Tyias Browning - is perhaps working with his least experienced pool of players since his appointment in August 2013.
"Last weekend only five of these boys started for their clubs, so that's a definite concern," Southgate said.
"In fairness, a few have been playing regularly, they just didn't start at the weekend, and we have two or three injuries now, and four with the seniors (Raheem Sterling and John Stones, in addition to Dier and Alli) who could be eligible for us.
"What will be exciting is that definitely in defence, we'll have a couple who haven't played for us before (Everton's Galloway and Tyias Browning), and it's great to see how they'll adjust to that because there's potential there.
"That's the nature of the Premier League at the moment
"It's a concern for Roy more than it is for me because the pool of players he's selecting from just seems to be getting smaller and smaller.
"For Roy, particularly, the lack of English players in the Champions League is a concern."
Three players - Chalobah plus Dominic Solanke and Lewis Baker - are on loan from parent club Chelsea at overseas teams, with the latter two at Dutch club Vitesse Arnhem. Southgate believes going abroad could prove the solution in the development of young English players.
"It's something which might start to happen a bit more," he said.
"The Championship is always an option, but to play top flight, in a slightly different style of football, is something clubs are looking at.
"Nathaniel's move (to Napoli) is a little more frustrating. He's out there and regularly involved but not starting so that one hasn't worked quite as successfully. That's always the risk with a loan.
"It's interesting that we've got two boys on loan in Holland, playing in their top flight. Last week they played against Ajax which is fantastic experience."