Manchester United left-back Luke Shaw has missed out on a place in Roy Hodgson's latest England squad for the forthcoming Euro 2016 qualifiers against San Marino and Estonia - and will instead be part of the Under-21 setup as he works his way back to full fitness.
Arsenal defender Calum Chambers also joins Shaw in Gareth Southgate's latest U21 squad, which was announced on Thursday morning.
The Premier League duo will participate in England's crunch Euro play-off tie against Croatia. The first leg takes place at Wolves' Molineux stadium next Friday, while the second leg is scheduled for Tuesday 14 October in Vinkovci.
Shaw dropped - despite return to fitness
Shaw, who completed a £27 million move from Southampton to Manchester United in the summer, made his first competitive start for his new club against West Ham last Saturday.
The 19-year-old impressed in the 2-1 win over the Hammers, but is still short of full fitness having only just returned from a hamstring injury sustained in August.
His fitness levels were also criticised prior to his injury by United boss Louis van Gaal, who told the player that he was not fit enough to carry out his demands. A special training programme was subsequently designed to help the former Saints' starlet reach the levels required.
Hodgson's surprise selection
But he looked much sharper on Saturday, which is why Hodgson's decision to demote the full-back to the England Under-21 side has come as a surprise, particularly with the Three Lions expected to win their next two qualifiers with minimal fuss.
Shaw has made a total of three appearances for the England national team after making his senior debut against Denmark in February, and was also part of Hodgson's squad for the World Cup finals in Brazil.
He made one appearance in the showpiece international tournament, in the 0-0 draw against Costa Rica, although England had already been eliminated from the group stages by that point having failed to beat either Italy or Uruguay.
Arsenal left-back Kieran Gibbs, 25, is expected to replace Shaw in the senior England squad. Hodgson will confirm his team later today.
England Under-21 squad in full
Goalkeepers: Jonathan Bond (Watford), Jack Butland (Stoke City), Sam Johnstone (Manchester United).
Defenders: Calum Chambers (Arsenal), Eric Dier (Tottenham Hotspur), Luke Garbutt (Everton), Ben Gibson (Middlesbrough), Carl Jenkinson (West Ham United, on loan from Arsenal), Michael Keane (Burnley, on loan from Manchester United), Jamaal Lascelles (Nottingham Forest, on loan from Newcastle United), Liam Moore (Leicester City), Luke Shaw (Manchester United).
Midfielders: Lewis Baker (Chelsea), Tom Carroll (Swansea City, on loan from Tottenham Hotspur), Jake Forster-Caskey (Brighton & Hove Albion), Will Hughes (Derby County), Thomas Ince (Hull City), Alex Pritchard (Brentford, on loan from Tottenham Hotspur), Nathan Redmond (Norwich City).
Forwards: Patrick Bamford (Middlesbrough, on loan from Chelsea), Saido Berahino (West Bromwich Albion), Harry Kane (Tottenham Hotspur), Cauley Woodrow (Fulham).