Pep Guardiola insisted Tottenham are genuine contenders for the Premier League title after seeing his unbeaten start as Manchester City boss come to an end at White Hart Lane.
The former Barcelona and Bayern Munich coach had won his first 10 games in charge of City before a midweek Champions League draw at Celtic was followed up with a maiden loss on Sunday.
Tottenham were good value for their win as an Aleksandar Kolarov own goal and a Dele Alli effort secured a 2-0 victory, with Erik Lamela unable to add the gloss to the three points as he saw a second-half penalty saved by Claudio Bravo.
City were harried as they attempted to play their passing game and they missed the incisiveness of the injured Kevin De Bruyne as the Spurs defence did a superb job of coping with Sergio Aguero and Raheem Sterling.
Guardiola, whose side remain a point clear of Spurs at the top of the table heading into the international break, believes the north London club can once again challenge for the title having run Leicester close last year.
"They were better," he said.
"They were the better team, that can sometimes happen.
"We play against a team who have had the same trainer for the last two or three years and last season were fighting until the end to win the Premier League.
"They have players with talent, we know how aggressive they are home and away but especially at home.
"We lost a lot of balls in the position that were so, so dangerous, they were one step in front of us today so we can just say congratulations to Tottenham, because when the opponent is better you just have to accept it and learn from that."
Asked if Spurs should be considered as serious title candidates, Guardiola said: "They were there last season. Why not?
"Same trainer, new players. In two or three years my team will be better so in that sense it is normal. Of course, here in the Premier League there are many teams who can achieve that and Tottenham is one of them."
While admitting he may have some regrets following his first loss at the City helm, Guardiola said the injured De Bruyne would have made little difference to the pattern of a game his side always looked second best in.
"Of course Kevin is a fantastic player but today, the way the play was, it wouldn't have changed too much," he added.
"Kevin doesn't win alone, we need to all be together, Tottenham didn't win because of one single player or two players.
"I think the individual performances depend on how the team plays, I'm not trying to say we lost because this guy made a mistake. __football is a game of mistakes."
Mauricio Pochettino's Spurs are now the only unbeaten side in the top-flight and sit second in the table behind City.
The Argentinian enjoyed his first-ever win as a manager against Guardiola when he guided Espanyol to a shock derby victory over Barcelona and he is now the man to inflict a first defeat of Guardiola's City revolution.
"I feel very happy and very pleased, the performance was nearly perfect," Pochettino said.
"To play a great team like Manchester City you need to do a fantastic job and for that I'm very proud for the performance and the work that our players showed today."
Pochettino stopped short of declaring the win his best since he took charge of the club in 2014, but the ex-Southampton manager was delighted with his entire team.
"I don't know," he replied when asked if the victory ranked as his best at Spurs.
"I think we have played some good games but it is true that in a collectively manner we worked very hard and all the players were fantastic on the pitch.
"I think it was a really exciting game, both teams played in an exciting way and we share a similar philosophy. I enjoyed it a lot from the touchline and the fans enjoy it a lot. Both teams, the mentality was to go forward, play __football and try and win the game."
Alli believes Tottenham made a "big statement" as they handed Guardiola his first defeat as Manchester City manager.
"It's massive," he told Sky Sports 1. "It was a big statement for us. We know what we were capable of and we knew there were going to be chances if we stuck to the game plan and when they came along we took them.
"I don't think there's any denying they are a brilliant football team and they do like to play the ball. We knew that if we got in their faces and kept working hard that we'd create chances.
"They're a great team and they're going to be up there at the end of the season but I think we showed what we were capable of."
Spurs are now the only unbeaten team in the Premier League and Alli wants to see that run continue after the international break.
He said: "Nobody wants to have that week off without the win so it was massive for us and it was important we keep going, keep fighting and just focus on the next game."