The last two seasons were grim for Spurs. This is as bad as it’s ever been | Jonathan Wilson

In March, Tottenham feared they might be relegated. So they spent a lot of money to bring in Roberto De Zerbi. He will probably never have as much power in a negotiation as he did then. The team improved and stayed in the league on the last day of the season. Since then, Spurs have spent £175m ($234m) more than they earned from sales to make the squad stronger. This seemed to send a clear message: the careful spending of the Daniel Levy era was over, and the club was now ready to spend money. But Spurs are bottom of the Premier League table as the season pauses for the first international break.

To an extent, the issue is confidence. On the opening weekend at Brentford, with a weird mishmash of a side, a team that was clearly undercooked, they were hammered 3-0 by much better-prepared opponents. That was not hugely surprising given how sensible Brentford’s transfer dealing had been and how early they had done it. More worrying was what happened the following week as Spurs, starting well before fading, lost 2-0 at home to Newcastle.

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Goalless draws against Nottingham Forest and Everton seemed to have steadied the ship. Their biggest problem seemed to be a lack of confidence. They were tentative in possession, indecisive when chances did come. The two goals they managed in their 3-2 defeat to Aston Villa on Saturday mean Spurs climbed above Coventry to second-bottom of the goal-scoring charts, but they are ninth for shots. That should be reason for frustration rather than panic; the goals will come eventually.

But there are more concerning things to have come out of Saturday’s game. The lack of confidence in front of goal seems to have curdled into something worse, a more general mental degeneration. Again, they started well. The Villa keeper Zion Suzuki made a string of saves. And then just before half-time Villa scored a shambolic goal. Micky van de Ven was off the pitch receiving treatment. Andy Robertson, in preventing the ball running out for a corner, gifted possession to John McGinn. A cut-back, a scuffed shot and Johan Manzambi was unmarked in the six-yard box to score. It was a horrible goal to concede.

The second goal Villa scored was also bad. A long kick from the goalkeeper was not cleared. Nicolas Jackson brought the ball down. Van de Ven did not close him down quickly enough. Jackson's shot hit Antonin Kinsky's hand and went in. The third Villa goal was a great strike into the top corner by Emi Buendía. He had time and space to set up his shot before James Maddison, who was supposed to be marking João Gomes, reached him. Maddison could perhaps have pressed him harder. The way he slightly turned his back as Buendía struck the ball is never a good sign. But this goal was at least as much about poor team shape as it was about Maddison's mistake.

Tottenham were somewhat unlucky. Robertson could have cleared the ball for a throw-in, or at least kicked it further down the line. Boubacar Kamara's cross was mishit and could have gone anywhere. Jackson will not always control a chest-high ball so well. Buendía has great skill, but he will not always find the top corner. Still, each goal came after some kind of mistake. The Premier League has many skilled players who will punish any error.

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De Zerbi spoke of Spurs being “too fragile”, by which he seemed to be talking both of their physicality and mentality. They have players returning from injury. Like so many clubs, they brought in players late. Preseasons have been curtailed, perhaps inadequate.

At first, people were impressed by the amount of money spent and the change in transfer policy. But now, doubts are growing about the quality of those summer signings. Is Sandro Tonali really worth £100m? Mateus Fernandes played for a team that was relegated. Jan Paul van Hecke would not be the first player to leave Brighton and see his performance level drop outside that carefully run club. Sávio and Omar Marmoush have struggled to get into the team at Manchester City. Sávio scored only two league goals in two seasons at City, and what happened on Saturday shows that his finishing has not improved.

People had thought this season could not be as bad as the last two for Spurs. They have no European games to distract them this time. The injury problems could not be as bad again. De Zerbi has already shown he can succeed in the Premier League. The club has spent money. And yet this season is as bad as any before it. In the past, a club like Tottenham could have called this a temporary dip, the kind of problem that would fix itself as the season went on. After the last two seasons, nobody can feel that sure anymore.

It is still very unlikely that Spurs could be relegated, and even a relegation battle seems unlikely. But the preseason hopes of qualifying for Europe already look far too optimistic. This will slow down the club's rebuilding process.

This is an extract from Soccer Desk, a newsletter from the Guardian US. Subscribe for free here.