England boss Sam Allardyce says he was “concerned” by previous squads including players inexperienced at first-team level for their clubs.
But he urged those left out of his squad for Sunday’s World Cup qualifier in Slovakia to “keep playing very well, and we’ll keep watching”.
Everton’s Ross Barkley missed out as uncapped West Ham winger Michail Antonio got his first call.
“It’s the hardest squad I’ve ever picked because it’s England,” he said.
“I hope that more and more very difficult decisions have to be made by the form of England players in the Premier League all breaking into the first team, playing regularly,” Allardyce added.
“It benefits us if players coming here would be very disappointed at not being in the squad, like Ross Barkley, and the players that aren’t picked in the 11 are then disappointed, and say ‘come on gaffer I deserve a place’ – that’s healthy for England.”
Former West Ham boss Allardyce said “the door will always be open” for Barkley, who has two goals in four appearances for Everton this season.
Marcus Rashford, who broke into the Manchester United first team in February before rising from England Under-20 to senior level under Roy Hodgson and featuring at Euro 2016, was left out of Allardyce’s 23-man squad.
Allardyce said the 18-year-old’s inclusion in England’s Under-21s “will be invaluable for us later down the line”.
“In the past it’s been a case of some of the players joining up who haven’t played that much for their teams. And that’s a bit of a concern,” Allardyce added, having spent nearly six weeks picking the squad for England’s first major match since exiting Euro 2016 in the last 16.
“We’ve looked at all avenues, what sort of pre-season they’ve had, what happened last season, this season, and looked at balance of the squad.”
Allardyce on… the captaincy
Wayne Rooney has held the captain’s armband since taking over from Steven Gerrard a year ago, with pundits expecting that to continue when Allardyce makes his announcement on Tuesday.
Allardyce said: “The captain leads by example and performances. He’s a captain on and off the field. Having been a captain myself, if you thrive on that responsibility and earn respect from players then the captain makes lot of decisions on field that you as manager can’t get on the pitch and do.
“You can shout as much as you want but it’s difficult to have an impact.”
England’s record goalscorer Rooney was employed as a midfielder during Euro 2016 under Allardyce’s predecessor Roy Hodgson. At Old Trafford this season under Jose Mourinho, Rooney has played in a deeper position behind the striker, and is listed as a midfielder in Allardyce’s squad.
“Wayne Rooney’s position has changed at Manchester United and that is where I will play him,” Allardyce said.
“Shall we call him an attacking midfielder? He’s an attacking midfielder at United. We name the squad to try and make it easy in terms of midfielders, defenders and forwards. Perhaps we should just name the squad next time.”
Antonio joined West Ham from Nottingham Forest for £7m in 2015 having played for Reading, Sheffield Wednesday and Southampton since starting his career at non-league Tooting & Mitcham. The 26-year-old has scored two goals in his past two games for the Hammers, including in Sunday’s 3-1 defeat at Manchester City.
“The quality of the player has shown through in every league he has played,” Allardyce said.
“The impact he had at the end of last season and the start of this, his attacking flair, his quality of final-third delivery, and his goal record from a wide position – I think that that journey is something that deserves to be in this squad.”
‘Important to entertain’
Allardyce was criticised by some fans while at West Ham for not playing what they called “the West Ham way”. But the former Bolton and Sunderland boss said he would want to entertain England fans.
“It’s about winning and entertaining – particularly at Wembley, entertaining the fans is very, very important,” he said.
“Maybe sometimes we have to dig one out here and there – let’s be resilient and tough. And let’s do what we need to do to get the result, something like Manchester United against Hull City. It all feels so good when you win it like that.
“Hopefully we don’t have to do too many like that but it feels nice when that happens.”