The flying Spaniard says Manchester City are fully equipped to tackle any opponent ahead of Monday night's top-of-the-table clash but admits Mourinho's teams are hard to beat
Having thrashed 10-man Tottenham 5-1 at White Hart Lane on Tuesday, City currently sit one point clear at the top of the table, two points ahead of the Blues.
Arsenal could go top this weekend with a win over Crystal Palace, but three points on Monday for the Manuel Pellegrini's men will see them regain top spot.
Navas claims the Etihad outfit are ready to take on any side in the league, but accepts that facing a Mourinho team is never easy.
"Mourinho's teams work especially hard, all the players," the 28-year-old told reporters.
"He has a special, winning mentality so it is always difficult to face teams that Mourinho manages.
“But we are working really hard and I think we are prepared to face any team.
"If you want to challenge for all titles, you have to be ready for these weeks or months that are very demanding when you have very important matches.”
City still boast a 100 per cent home record this season having netted 115 goals in all competitions, and Navas says he is loving life in Manchester.
"I am really happy here in England," he added. "I have settled down very, very well both on a professional level and personal level.
"All of my team-mates help me very much in adapting to a new league, a new style of football.
"On a personal level, I have my family here, my wife, my daughter, so I am extremely happy.
"I love football and enjoy playing football. That's why I came here. I am very happy and cannot complain.
"We have to keep working like this, working really hard and, if we do it like this, then we are going to get the same results."