The Manchester City defender's permanent move to Schalke was confirmed on Wednesday afternoon.
The 21-year-old, who featured for Roberto Di Matteo's Schalke side in the Champions League at Real Madrid on Tuesday night, has impressed during his time in the Bundesliga and appears to have a very bright future ahead of him indeed.
Which is exactly why many - certainly not all but what appears to be a majority - Manchester City supporters have been disappointed by the news Nastasic has been allowed to leave the Etihad Stadium for good.
The Serb was previously on loan at Schalke and, while fans were not surprised the loan deal was made permanent, several have questioned the thinking behind the decision.
Did Nastasic really fall so far from grace in terms of his performances after initially impressing at the Etihad? Is Manchester City's defence really better without him? Are Eliaquim Mangala and Martin Demichelis good enough upgrades?
Without making too many rash assessments, it's safe to say the 21-year-old will be missed by many at City - especially judging by the reaction to the sale from Manchester City supporters on social media.
Here's a selection of what fans are saying...
Think Mangala will be a good signing, but it was £32 mill we could have spent elsewhere, when we had Nastasic. #mcfc— Daniel Oakes (@DpoCTID) March 11, 2015
All the best Matija Nastasic. Your debut at Madrid for us and your performance last night shows you're a top player. Sad you've gone! #MCFC— Carl (@MCFCarl) March 11, 2015
Disappointing that we let Nastasic go, massive potential and on his day far better than Demichellis, was a ready made replacement #mcfc— Rahul Chadaga (@rahulioc) March 11, 2015
Seriously, Nastasic didn't have a great 13-14, but I do think we're making a big mistake here. And I'm a Mangala fan. #mcfc— David Mooney (@DavidMooney) March 11, 2015
Good luck Nastasic. Never given a chance to play. Pellegrini made a mistake in letting him go #mcfc— Piyush (@PiyushMCFC) March 11, 2015
Nastasic and Savic replaced by Mangala and Boyata still here, throwing away money. #mcfc— Craig Cassells (@CraigCassells01) March 11, 2015