(REUTERS) - Manchester City manager Pep Guardiola said his side were not clinical enough in their 1-0 defeat at Tottenham Hotspur on Sunday (Aug 15) but insisted that he was "delighted" with the attacking options in his squad.

A second-half goal from Son Heung-min meant reigning champions City fell to a surprise loss as they began the defence of their league crown with an under-par display.

City and Guardiola have now lost all four of their games at Tottenham's new stadium without scoring, including three in the Premier League.

"In general, we showed a good spirit and good intention and we arrived in the final third many times, but we could not be clinical enough. Son scores and we lose," the Spaniard said.

"We have the same players as last season. I'm so delighted with the same guys who scored a lot of goals. We are good enough to create chances and score goals - we will do it.

"We are one against one a lot. But in the end we could not dribble, shoot and score goals. But the way we started showed me the team is there."

Guardiola's side will host Norwich City on Saturday.

New £100 million (S$188 million) signing Jack Grealish sparkled briefly on his debut but faded along with his teammates against Spurs.

Midfielder Grealish, a British-record signing, made a lively start and almost earned a penalty with one jinking run ended on the edge of the area by Tottenham youngster Oliver Skipp.

But it turned into a frustrating afternoon for the former Aston Villa playmaker and he marked his debut not with a goal or an assist but a yellow card.

He was not the only City player to struggle as few of Guardiola's side were in top gear against a Tottenham team who grew into the game and deserved the win sealed by Son's 55th-minute counter-attack goal.

Even with an array of attacking threats on the pitch and £340 million worth of talent on the bench, City were listless and lacking a cutting edge.

If anything the display will make the signing of Tottenham's absent striker Harry Kane even more pressing for the City hierarchy - whatever the cost now that Sergio Aguero is no longer an option for Guardiola.

The manager would not get drawn into the Kane debate, but praised new boy Grealish.

"He was excellent. He played with a personality and created chances. Unfortunately we could not win for him for his debut but he played really well," the Spaniard said.

"In terms of give me the ball he doesn't lose the ball, he is so dangerous close to the box."

City became only the third champions in the Premier League era to lose their first game of the new campaign and some of their players looked off the pace while Kevin de Bruyne was left on the bench until late on.

"Kevin de Bruyne has not done one full training session, he needs to train. He will need time to play 90 minutes," Guardiola said.

"We are the same people that won the Premier League and we make very good things and it's normal."

"Spurs are a tough rival for us, always I have the feeling that we are good here but we cannot get results because they punish you in transitions," he said.

"Most of the players have 90 minutes in the legs, we have a long week to prepare to face Norwich and hopefully the players can come back step by step.

"I see very, very good things. I know the result is not good but I saw many, many good things that will help us in the future to get better."