The Manchester United defender has been capped at U16, U17, U18 and U19 level, but has not been involved with the Three Lions since February 2013 when he featured in a 3-1 win over Denmark for the U19s.
But his impressive pre-season campaign convinced United boss Louis Van Gaal to select him for all three Premier League games so far this season – and won him a first call-up to Gareth Southgate’s squad.
"Pre-season went well for me, I concentrated on what I needed to do and I’ve had a good start to the season as well, so it was nice to get called into the Under-21s and hopefully that continues," said Blackett, who is hoping for an Under-21s debut in the games against Lithuania and Moldova over the course of the next week.
"It’s been very good so far, I’ve enjoyed training and have just got to try and push on and prove myself at this level as well.
"This England squad Is quite similar from some of the other age groups I’ve played in so I know a lot of the lads from previous games and now we’re all here together so it’s been good."
The squad met up at St. George’s Park on Sunday evening to begin their preparations for what are the final two Euro qualifiers for Southgate’s team ahead of next month’s play-offs.
They fly out to Kaunas on Thursday ahead of their first match with Lithuania on Friday evening before heading on to Tiraspol. There they take on Moldova on Tuesday evening.
And while the 20-year-old is looking forward to the journey east, he is anticipating two tricky encounters with both Lithuania and Moldova undoubtedly keen to topple the confirmed group winners.
"I think they’ll be tough games, as all internationals are," he added.
"They will have different styles of playing and different ways of setting up so hopefully we’ll learn a bit and have good games against them.
"I just want to do my best while I’m here in training and keep progressing, so that when it comes to the games I’m going to be ready."
Away from England duty, the Manchester-born centre-half was an interested observer throughout Monday as he followed the transfer deadline day saga involving United and their loan signing of Colombian star Radamel Falcao.
That new addition to the Old Trafford ranks follows swiftly on from the record purchase of Angel Di Maria from Real Madrid last week, something which has left the former Blackpool and Birmingham City loanee pinching himself at times.
"It’s been unbelievable so far with the players that have come in," admitted Blackett, who has been with United since he was eight.
“Training and working with these players is a part of my career that I’ve just got to look forward to.”
"It should be enjoyable, there’s a whole new squad there now and we’ll be ready to start again after the international break.
"As a centre-back, training and working with these players is a part of my career that I’ve just got to look forward to and do my best.
"The manager told us all, right from the word go really, that he’s not scared of using the young players so we’re all ready to go and try to prove that we can play at this level.
"It’s been good for all of us."