The England duo failed to make it into Roy Hodgson's 21-man squad for the upcoming Euro 2016 qualifiers, but instead were called in the under-21s for their Euro 2015 qualifier against Croatia.
And Middlesborough legend Gareth Southgate has urged them not be be downhearted by their exclusion from the senior squad.
"It shouldn't be seen as players coming back down being some sort of punishment. We have got to make that movement between the squads more fluid.
He said: "It's a positive message, to show they are prepared to come and join in with the rest of the group is important.
"Roy (Hodgson) and myself work very closely every time there's a squad announced and clearly Luke and Calum have been around the senior squad already.
"The fact it's a play-off game Roy was keen that those who he didn't think would start for him were with us. That's the joined-up thinking we're trying to put in place.
"The boys have to come and have the desire to come and do that. They understand the situation because getting to the finals is important."
Both youngster have had a taste of what it is like to be in the senior England squad, with Shaw being selected for the summer World Cup and Chambers receiving his debut in the 1-0 win over Norway early last month.
The Southampton academy pair both made big money moves away from the club during the summer; Shaw joined United for £30 million and Chambers signed for Arsenal for £16 million.
And whilst Chambers has flourished with the Gunners the same can't yet be said for Shaw at United. The full-back was criticised by United boss Louis van Gaal for his fitness in preseason, and then suffered a hamstring injury which meant he missed the start of the new season.
Shaw made his Premier League debut for United last weekend in the 2-1 home win over West Ham and looked relatively solid and composed throughout.