Otamendi, who has featured in 18 of City’s 19 Premier League games and weighed in with five goals, has been in inspirational form for the Blues and a defensive rock all season.
“We have a superman in the team,” he said.
“Otamendi helped us absolutely. If I would like to point to a player who deserves respect for what we have done so far this season, it is Otamendi.
“Always fighting. He is a huge competitor and one of the best I have seen in my life. So important. Without him, it would have been impossible.”
With 1,734 passes made so far, Otamendi tops the Premier League list ahead of team-mate Fernandinho.
“Being a central defender in our team is not easy,” said the boss.
“They have to do more than just defending. It is so demanding. This kind of thing can only happen when you are brave and have courage.
“People thought we couldn’t do these things. Nico is reading the situations. Where to pass the ball, when to play it and I am really impressed.
“What you have to do when the opponent jumps or doesn’t jump. Where are the spaces? He's reading it really well. I am so happy for him. He deserves all our respect."
Commenting on previous players he has managed Guardiola added: “At Barcelona we had Rafael Marquez, Gerard Pique and Abidal and Carles Puyol, and Bayern with Jerome Boateng and Holger Badstuber were able to do that.
“Just to convince them is not so complicated. Then it is training and process. He is so clever. For John Stones, it is easy for him (with those skills). What I admire the most is that maybe it's not his (Otamendi's) strength point but, but he tried and he’s doing it.”