Defending champions City played to the title in record-breaking fashion under Guardiola last season, finishing 19 points clear of second-placed Manchester United.
But with the top five teams separated by two points after the first nine games, Guardiola says his league leaders will have a far tougher fight on their hands to defend their title this season.
“I don’t have doubt about that. Two points difference in five, six teams. It’s strong,” Guardiola told a news conference on Friday.
City, who are top on goal difference ahead of Liverpool, face fifth-placed Tottenham Hotspur at Wembley on Monday and Guardiola is wary of the tactical surprises his opposite number Mauricio Pochettino is capable of springing.
“Spurs play with five at the back sometimes, sometimes diamond, sometimes 4-2-3-1. They can use it and change again,” Guardiola added.
“When you know a team does the same thing, it’s easier to control it… they can change it. You have to be prepared.”
Wembley will host an NFL game between Philadelphia Eagles and Jacksonville Jaguars on Sunday, raising concerns about the condition of the pitch, but Guardiola said his team would have no complaints about the playing surface.
“It is what it is,” he added. “It’s not necessary to complain about that. We have to adapt quickly and try to figure out the pitch will not be in perfect conditions and adapt. We have to do it.”