The teenage winger surprised many when he moved to Germany last year, but a bold call has been handsomely rewarded.
Those opportunities were unlikely to have come his way had he remained on the fringes of a star-studded squad at the Etihad Stadium.
Sterling, a current star for reigning Premier League champions City, told reporters of Sancho’s ambition: "For someone so young to back themselves to go abroad is a credit to them.
"To go abroad so young and back yourself, that shows a lot about the person. He could have taken the easy route and stayed at City but he saw himself developing better.
"That's what it's about in football - you have to judge your own situation and he did that perfectly and all credit to him.
"He has knuckled down in Germany and, when you're that age, it's probably something you need. To have that seclusion and be by yourself a bit and to concentrate solely on football. I'm really happy for him."
Sterling has also hailed Sancho's work ethic and is not surprised the 18-year-old has eased seamlessly into international football.
The highly-rated youngster replaced Sterling with 12 minutes remaining in England's goalless draw with Croatia on Friday to become the first player born this millennium to represent the Three Lions.
Sancho impressed during his short cameo and Sterling says he always knew that an exciting prospect had what it takes to succeed at the highest level.
"He is a really good talent and someone I've thought highly of since the first time I saw him at Manchester City when he was training with us in pre-season," he added:
"I thought highly of him - his work ethic and what he does with the ball. I know him really well and he's someone that is really modest but when he's on the field he wants to express his ability."
Sancho and Sterling will be hoping to see more minutes for their country on Monday when England take in a Nations League clash with Spain in Seville.