The North London club backed De Zerbi, 47, with over £300 million in new signings this summer following two dismal seasons in the Premier League.
So far, that investment in the squad and manager hasn’t paid off, with Spurs down in 17th having failed to score a single goal in their first four Premier League games of 2026-26.
Tottenham were held to a 0-0 home draw with Everton on Saturday, and after the game, De Zerbi admitted his side are lacking 'confidence' and 'physical conditioning'.
"Now is one of the moments in football when you rebuild a team, when you start late because we started together with Marmoush, Sávio, (Dominic) Solanke, (James) Maddison two Thursdays ago," he said.
"Now I think we played very well in the first 30 minutes. Then maybe we lost energy because our physical condition is not the best and we are working for that.
"We didn't shoot for the quality of play we showed. We have to shoot more time on goal. We have to work and analyse the decision-making because we made too many wrong decisions but I think we played well.
"After the World Cup with many players involved in the World Cup, it is like this. We suffered two or three injuries -- Mateus Fernandes, Micky Van de Ven in Australia (during pre-season) and they couldn't work and other injuries like Solanke.
“I am not positive or negative, I am realistic. If you play like this for 30 minutes it is because you are capable to play football. We have to extend that to 90 minutes and then stay more focused on the last 25 minutes.
“Today, if we would have won, now we would speak about a completely different game."
De Zerbi then referenced the state Tottenham were in when he joined, replacing Igor Tudor following his disastrous 44-day tenure.
"I came last season when the s*** was like this (hand above his eyes), you know? S***, I repeat. And I've always been, not positive, but realistic,” he added.
"Now I explained, I'm sorry for the results, but it's not immediate, no? Not the improvement, not immediate to make a team.
"Today we played as a team. We didn't score, we didn't win, but today and Nottingham I think we played as a team.
“And I can't say nothing as an attitude, as a behaviour of the players, no, no. I said to stay calm, maybe to not lose the confidence because we are not scoring, we are not winning.
"Stay calm, improve, work hard and individually try to understand where is the improvement, no?"