The Argentine has left City to join Benfica having won two Premier League titles, an FA Cup, four League Cups and two Community Shields during his time at the Etihad.
And in an exclusive interview with CityTV, he described his pride at what he has achieved in Manchester – and praised the staff that have helped him along the way.
“They were five wonderful years,” he said. “Not just in a footballing sense, but also at a Club where they treat you in the best way possible, from the chefs to the kitmen, through to the backroom staff.
“I’ve worked under two different sets of backroom staff, and I have to give my thanks to all of them, because you learn so much from each of them.
"Today I am so grateful for being part of this five-star club.
“We have gone through different phases, but it has all been positive. I’ve had the opportunity to win two Premier Leagues, to win the Carabao Cup, the FA Cup and the Community Shield.
"If you win titles, it’s because you’re doing things well. I’m happy to have enjoyed these moments and I am more than grateful.”
For a player who has won nine trophies in English football, picking a highlight is difficult for Otamendi.
From the Centurions season to the Fourmidables campaign, there have been some sensational highs for Nico to treasure as he embarks on his new challenge at Benfica.
But for the tough-tackling defender, it’s the relationships he fostered at City he will remember most.
"Of course some of the favourite memories will always be the titles won, they are so important," he said.
"But my favourite memory will be with the people who work here. Since I arrived with my family, they were always there for us and that is so important.
"From Txiki, who was here to welcome me to the club, and Ferran, that is all priceless.
"What the club does for the players so that we don’t need anything, so our families are comfortable, so our children are happy at school - it takes a weight off the shoulders of the players, and those things are the most important for me."
And, finally, the man known as The General had this message for the fans.
“I want to show my gratitude. Since my arrival they have always treated me well, from the people who bump into me in a service station or in a supermarket, they have always been so kind, saying nice things to me.
"I hope they are happy, I gave everything I could to the Club, and I hope the success keeps coming.
"I send all my love to the fans.”
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