Roberto De Zerbi said that Tottenham are undercooked and lacking fight after they slumped to a 3-0 defeat at Brentford.
Spurs' expensive summer rebuild was shaken to its foundations by rampant Brentford on an alarming opening day for De Zerbi.
The new-look side showed the same old flaws as goals from Keane Lewis-Potter, Vitaly Janelt and Michael Kayode saw them deservedly beaten.
De Zerbi, parachuted in to save Spurs from relegation last season, said: "For many reasons I think we are not [a] team yet. We are not at the right point in physical condition.
"But no excuse. When you are building a new project I don't want time, but we have to pass through these problems.
"I believe in my players, my club and myself. I think we are working well but we are late for the start of the Premier League.
"It's a step we have to improve quickly. We could fight stronger than we did today and we lost too many duels.
"The target is to become [a] team. To find the spirit, the soul, is a process."
Spurs, who gave debuts to five players, look set to top the £300 million ($351m) mark on new faces this summer once they complete deals for Savinho and Omar Marmoush.
But it was Brentford's marquee signing Mamadou Sangare, at the comparably reasonable price of £41m ($56m), who provided the early dividends as the catalyst for a superb Brentford win.
"It's pretty impressive on a lot of fronts. You never truly know from preseason what you're going to get," Brentford coach Keith Andrews said.
"But it felt like we were in a good spot and we produced a pretty good performance."
Brentford beat a host of clubs to the services of Sangare, who set up two goals and looks like a ready-made Premier League star.
"More of the same from him, hopefully," Andrews said. "It's been nice working with him and the club deserves a lot of credit for getting that deal done because he could have gone elsewhere.
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"He adds to an already quality midfield that we have. I really enjoyed his performance today.
"You never truly know in a different league, with a different language, but he's a humble young man who looks very hungry."
Last season Brentford missed out on European qualification only on goal difference, yet they still do not get the credit they deserve in some quarters.
"That's the beauty of this game," Andrews said. "It's about journeys, it's about stories, it's about narrative. You've just got to go with it, haven't you?"
