Spurs have taken one point from their opening four Premier League games
Tottenham manager Juande Ramos has said it could take more than 10 games for his winless side get back on track.
The big-spending Londoners are bottom of the Premier League after their worst start to a season for 34 years.
Ramos, speaking ahead of Spurs' Uefa Cup tie against Wisla Krakow, said: "We need to improve, little by little. It could be 10, 12 or 15 games. No limit.
"Yes, I am worried because we need points. We have a good squad and, I'm sure in the future, we'll be better."
Tottenham have taken just one point from their opening four Premier League games and their 2-1 defeat to Aston Villa on Monday condemned them to the bottom of the table.
Ramos admitted a host of deadline day transfers, with duo Vedran Corluka and Roman Pavlyuchenko arriving and Dimitar Berbatov departing for Manchester United, had disrupted his squad.
However, the former Sevilla coach said he was confident results would improve and that new signings such as Luka Modric, Giovani dos Santos and David Bentley, who have so far been below par, would settle.
The worst thing for us was losing Berbatov at the last moment and we didn't have time to sign a new player
"To only have one point is a difficult situation to be in," he said.
"I'd say to the supporters that they need to have confidence in the team. We have a good squad and, I'm sure in the future, we'll be better.
"I don't know about top four, but anything is possible. There are 34 matches left to play.
"The fans, myself, the club - we want the best performances quickly, but we need to be patient. This process takes time."
The club's sporting director Damien Comolli, who scouts and signs players for Ramos, has come under criticism, particularly as Spurs are short of options up front following the summer departures of Robbie Keane and Berbatov.
But Ramos and first-team coach Gus Poyet have defended Comolli, with Ramos declaring: "Everyone is together in the club.
"The decisions are made together. Not one person is responsible. Whether it is winning or losing, we do things together.
"I think in some positions we are better than last year, in others we are worse. The squad is the squad.
"For me, the big problem is adaptation and the need for time. The worst thing for us was losing Berbatov at the last moment and we didn't have time to sign a new player. But business is business. It was impossible."
Tottenham have a chance to resurrect their season against Polish side Wisla Krakow in the first round of the Uefa Cup on Thursday.
And Ramos admitted that winning Uefa Cup would be easier than finishing in the top four.
"I never think about losing. In my head, that's not possible. In football, you can win or lose. But I'm not thinking about losing," he said.
"We want to win all the matches, but it's harder in 38 league games to finish above Chelsea, Manchester United and Liverpool. In the cups, you can win five or six matches and win a trophy, so that is easier."
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