Guardiola opted to step down as City boss at the end of last season - despite having a year left on his contract - with the Catalan coach winning 20 major trophies as part of an incredible decade in Manchester.
Enzo Maresca has since returned to the Etihad Stadium with Guardiola's former assistant stepping in as his replacement.
As the dust continues to settle on Guardiola moving on, Nunes has revealed the emotion felt by players and City staff, on the day Pep bid them farewell.
"We knew there was a chance he could leave. But, until he actually said it, you don't know if he actually will go.
"He spoke to us all. It was a very emotional day, a lot of people were crying, as it's very hard to say goodbye to someone who has done so much for us and given so much to the club.
"He put the club on a level that seems unreachable to do again."
Guardiola is expected to take a break until the end of 2026, before deciding on his next role, after confirming his call not to accept the Italy national team job last month.