Burton-on-Trent - Marcus Rashford needs to play regular first-team football for Manchester United if he is to regain a place in the England squad, national manager Sam Allardyce told reporters on Monday.
Rashford, 18, made his first appearance of the season for United as a substitute at Hull City on Saturday and tapped in a 92nd-minute winner to give Jose Mourinho's side a 1-0 victory.
But his lack of game-time saw him drop down to England's Under-21 squad and Allardyce says he will not earn a senior recall if he is not in United's first team.
"If he's breaking into Manchester United's team, he will be in my squad," Allardyce said during a press conference at England's St George's Park base in Burton, central England.
"But because of his inclusion only as a substitute - as good as it was against Hull City - I think that the value of having probably a full game with Gareth (Southgate, Under-21 manager) will be invaluable to him and, later on, for us.
"A bit like Harry Kane and people like that in the past."
Rashford went to Euro 2016 with England after scoring nine goals in his first 18 United appearances, but he is now preparing for the under-21s' home game with Norway a week on Tuesday.
"He made a massive impact last season, yes, but he's only a young man," Allardyce added. "Let's not heap too much pressure on him just yet. Let him go and have a feel playing for the Under-21s.
"Hopefully he's a star for them, scores goals for them and gives me that decision next time around on the next squad I pick."
Rashford's United team-mate Wayne Rooney, who set up his goal at Hull, echoed Allardyce's remarks.
"It's still important for his development to go and play with the Under-21s," Rooney said, in comments published by several British newspapers.
"It's important that he gets games because he hasn't played that much. I think it will be good for him.
"He knows that and he understands that and his time will come and he will get his chance for Manchester United and England."
Allardyce takes charge of England for the first time on Sunday when they play Slovakia in Trnava in their opening 2018 World Cup qualifying match.