André Villas-Boas cannot be blamed for Manchester City's opener, scored by Jesús Navas after 13 seconds following a poor Hugo Lloris clearance, but from then on Tottenham were astonishingly open, constantly leaving their centre-backs exposed and raising serious questions about their approach.

Spurs' first intention should have been to protect their centre-backs – Michael Dawson consistently looks uncomfortable in a high line while Younès Kaboul was making his first league start for 15 months. They were up against the league's in-form strike partnership, Sergio Agüero and Alvaro Negredo.

Although City essentially played a 4-4-2 formation in possession, Negredo dropped back to support the battle against Tottenham's three central midfielders. That left Agüero up front, able to use his pace in behind the Spurs defence. Negredo would sprint forward to join him and his deeper position was taken up by Samir Nasri who drifted inside from the left dangerously.

While Sandro played a defensive-minded role and attempted to protect the defence, he was exposed against midfield runners because Paulinho and Lewis Holtby were bypassed so easily. Sandro's superb last-ditch challenge on Nasri early on demonstrated his tackling ability, but he was forced into a succession of desperate challenges to stop quick counter-attacks. He endured a truly disastrous first period, which included an own goal and a vomiting incident, and he was also handicapped by a 20th-minute caution. After that he needed Paulinho to sit deep alongside him to share the defensive midfield duties as Spurs tried to ease their way back into the contest.

Manchester City's front four sprung forward quickly, exposing Spurs' lack of defensive cover. Photograph: Guardian/Graphic

There were other problems for the centre-backs – Jan Vertonghen and Kyle Walker charged forward from full-back, but this forced Dawson and Kaboul to defend the width of the pitch when City counter-attacked quickly. Walker was helping Spurs make progress down the right, and his strengths lie in his attacking ability, but Vertonghen is a natural centre-back and Villas-Boas could have used him more cautiously, giving Spurs cover at the back.

Another problem was Spurs' centre-backs splitting in possession, with a midfielder dropping into defence. This makes sense when building passing moves against a two-man strikeforce, but it had disastrous consequences when Spurs were caught out in the transition between the two systems for City's second goal – Holtby, on paper Spurs' most attacking midfielder, briefly found himself in the middle of a back three and failed to track Agüero.

Amazingly, Spurs dominated possession. But City were entirely happy with this situation because it allowed them to draw Spurs up the pitch, before breaking powerfully. Whether it was Agüero sprinting in behind, Jesús Navas attacking down the right or Nasri and Yaya Touré storming through the centre, the space afforded to City was astonishing. Villas-Boas' decision to go 4-4-2 at half-time, with Emmanuel Adebayor replacing Holtby, opened up the game and exposed Sandro, Dawson and Kaboul even more.

Villas-Boas' coaching philosophy cannot be dismissed on the evidence of one match. But a touch of pragmatism and caution was required – this shouldn't have turned into such a humiliation.