Gareth Southgate says Conor Gallagher "deserves" his England chance after the Chelsea midfielder received his first senior call-up.
The 21-year-old has been rewarded for a stellar campaign on loan at Crystal Palace, having scored four goals and assisted two for Patrick Vieira's side.
Gallagher has previously represented England at U-17 through to U-21 levels.
What did Southgate say?
Reflecting on Gallagher's inclusion ahead of Monday's World Cup qualifier in San Marino, Southgate said: "We've been very impressed with him.
"We've tracked him for a very long time in his loan spells at Charlton, Swansea - we knew the staff there very well - at West Brom and now at Crystal Palace so in each loan he has done extremely well.
"He has started the season very well with Palace. We talked about him when we named the original squad as somebody we were keen to keep an eye on, and I suppose it's one of the benefits of being with the Under-21s because it was an easy transition for us to bring him across."
What else has been said?
As well as anouncing Gallagher's arrival, England also confirmed Jordan Henderson, Jack Grealish, Raheem Sterling, Mason Mount and Luke Shaw will all miss the San Marino clash.
A statement said: "Henderson and Grealish have returned to their respective clubs for further assessment on injuries.
"Sterling will miss out owing to a personal matter while Mount (dental surgery) and Shaw (concussion) will no longer link up with the squad."
Gallagher established himself as a bright prospect in the Chelsea academy before getting his first taste of senior football with Charlton Athletic and Swansea City in 2019-20.
After impressing in the Championship, Gallagher made the step up to the Premier League last season when he became a regular with West Brom.
The Baggies were relegated but Gallagher's form earned him another Premier League loan move, this time to Palace.
England on the brink of World Cup
Gallagher will join up with Gareth Southgate's squad after they defeated Albania 5-0 on Friday.
That win put them on the brink of the 2022 World Cup, with the Three Lions needing just a point against minnows San Marino on Monday to qualify.