The pace at which Raheem Sterling ascended through the England ranks was a hot topic last month, as Brendan Rodgers preached caution just days before Roy Hodgson announced that the 17 year-old winger would be joining the full England squad for their Wembley date with the Ukraine. That call-up proved to be more about numbers than anything else--to Hodgson's credit, he made it very clear ahead of the match that Sterling's inclusion was an opportunity to have him with the senior setup and nothing more, and while he made the bench, there was never really a threat of playing.
His selection today in the U21 squad for their two-leg playoff against Serbia isn't much of a surprise, then, even if it means his cameo with the U19s was short-lived. This seems more a middle ground for Sterling, as ability-wise he's outgrown the U17s and probably the U19s, but it's not the full international level that, while not likely to overwhelm him on the pitch, presents a complete package for which the player might not yet be ready.
He's included along with three other Liverpool squad members, two of which--Jonjo Shelvey and Jordan Henderson--are no strangers to U21 competition and another in Andre Wisdom who, like Sterling, is rising through the ranks steadily for both club and country. This is the last step before the full European Championships for the U21s, and it's possible (and in the cases of Henderson, Shelvey, and Sterling, very likely) they'll play a part in a qualifying tie that kicks off on October 12th in Norwich