Sancho, 18, has been named in a 25-man squad for the Nations League matches against Croatia and Spain alongside fellow first-timers Mason Mount and James Maddison. Like many talented players before him such as Christian Pulisic and Marco Reus, Jadon Sancho contract in Borussia Dortmund is extended till 2022.
"He's a player that is explosive, is really creative in the final third, and has had a big impact in terms of assists in the matches he has played, can score goals and has had a big impact in our junior teams in the last couple of years".
"You never know with young players what they are capable of until they have an opportunity", the manager told a news conference at the national St George's Park training center.
"In a different era it would take 100 appearances in the top flight before they got a cap but we live in different times".
"Okay, we've got to think differently about it, be bold in some of our decisions and we'll get some of those right and some we won't get right". We have done that over the last few years. These calls however are likely to be resisted by Southgate for now, in favour of letting Sancho improve with Aidy Boothroyd's Under-21 side first.
"Very often we hold youngsters back a bit too much", said Southgate, who previously coached England's under-21 team. I hope we can continue to excite the English public'.
Dembele, a similarly tricky and exciting forward, has since gone on to win the double with Barcelona and won a World Cup winner's medal this summer with France, feats Sancho will be dreaming of emulating with Dortmund and England.
Ross Barkley and Nathaniel Chalobah are also called up. "He's been courageous enough to go overseas and play", added Southgate.
"This year he's started the season in the team at Chelsea. I'm always trying to find that balance, the messaging has to be correct, but it's good for their development to see how they train with us".
"As I say, one or two of those opportunities might not have been there if we'd had other players available".
"Then they have got to fight for their place in the under-21s squad then because that's not bad either".
"Where actually if you don't have a target like that... we started to work back from there".
Southgate spoke well of Daniel Sturridge after overlooking the Liverpool striker and insisted the door is still open to Joe Hart, despite plumping for uncapped Marcus Bettinelli and Alex McCarthy along with Jack Butland and Jordan Pickford.