We are now a third of the way through the 2018/19 Premier League season and things are starting to get interesting at the top and bottom end of the table. Chelsea's defeat to Tottenham Hotspur showed Maurizio Sarri's team aren't ready for a title challenge, while Manchester City's strangely unconvincing 4-0 win at West Ham will have encouraged Liverpool fans.

Further down the table a big win for Fulham suggests Claudio Ranieri is the man to lift the London club to safety, plus victories for Huddersfield Town and Newcastle United made the relegation battle look tighter than ever.

Here are three things we learnt from the weekend action:

1) Spurs build on Everton's template with two new ways to stunt Chelsea

Chelsea were held to a 0-0 draw by Everton before the international break thanks largely to Gylfi Sigurdsson's role in keeping Jorginho quiet; Sarri's team rely too heavily on the Italian, which is why Spurs followed suit by sticking Dele Alli on Jorginho on Saturday.

But Tottenham did a lot more than that. Mauricio Pochettino's 4-3-1-2 formation perfectly capitalised on the tactical flaws in Sarri's system, most notably by swarming central midfield in the area around N'Golo Kante. With Harry Kane and Dele dropping off to join Spurs' midfield three, the centre-left zone was overwhelming for Chelsea's France international, who isn't good enough technically to grab control of the game. It is here that Spurs consistently regained possession, turning the screw to suffocate the visitors.

Spurs also dominated the flanks thanks to Chelsea's one-dimensional attacks. Sarri needs to implement greater variation than constantly seeking a passing line of Jorginho to Eden Hazard, but he also needs to encourage runs in behind and longer vertical passes. Chelsea are always building slowly with their backs to goal, which is why the Spurs full-backs could consistently push up to get touch-tight to Hazard and Willian; there was no threat of Serge Aurier or Ben Davies being caught out by an overlapping Chelsea player, allowing them to commit to pressing on the flanks.

2) Jurgen Klopp needs to find a playmaker for his new possession-centric style

The Liverpool of last season – frenzied pressing, quick vertical passes into the front three – didn't need a playmaker in the mould of David Silva or Christian Eriksen to link the midfield and attack. But Jurgen Klopp's shift to a more prosaic possession style this season, coupled with opponents increasingly using a deep defensive block, means Liverpool now seriously miss a player who can turn in possession and slip clever passes through the throng of bodies.

This was more obvious than ever in the first hour of their 3-0 victory over Watford, in which the hosts easily stunted Liverpool with their narrow, box-shaped 4-2-2-2 formation. The two strikers tucked in to block the lane through to the front three, while Jordan Henderson and Georginio Wijnaldum came deep to receive the ball from the centre-backs... only to find no options further forward.

But Liverpool finally made the breakthrough when Roberto Firmino dropped right back, taking the ball and spraying it out to Andrew Robertson before steaming forward and collecting it again in the final third. His neat through ball to Sadio Mane set up the crucial opener. Firmino, then, could be the Silva-type Klopp needs, although it will require a major change of position for the Brazilian. He has the talent to retrain, but would Klopp accept losing his striker?

3) Kolasinac and Iwobi star in Emery's new 3-4-2-1 formation

Unai Emery's surprise move to a 3-4-2-1 formation for the trip to Bournemouth was probably done for two reasons: first in anticipation of Bournemouth also using this system (lots of Premier League managers have found mirroring the Conte-inspired system the best way to counteract it) and second to add defensive support on Arsenal's left. Sead Kolasinac had looked error prone recently, and so it made sense to free him for a more attacking role with a third centre-back covering behind.

Although it didn't quite work out as planned – Bournemouth had plenty of chances in the first half - it was interesting in an attacking sense. Alex Iwobi's positioning as an inside forward seemed to draw Bournemouth into a narrow shape, primarily because their 4-4-2 meant central midfield was light on numbers unless David Brooks and Ryan Fraser tucked inside to help. However, this meant leaving space on the outside for the wing-backs to drive into, which is exactly what happened for both Arsenal goals.

Iwobi's interactions with Kolasinac eventually forced Eddie Howe to switch to a 3-4-2-1 in the second half (there's that mirroring strategy in action), so that a spare centre-back could go and meet Iwobi without compromising shape. Unfortunately for the hosts, when Simon Francis did this Iwobi managed to turn and feed Kolasinac, who easily wriggle free of makeshift wing-back Ryan Fraser and set up the opener. Iwobi to Kolasinac assisted both Arsenal goals.

Best of the Week – Ciaran Clark

Newcastle United's hard-fought victory at Burnley on Monday night was vintage Rafa Benitez: two set-piece goals and some powerful last-ditch defending was enough to win a game in which most managers would not have been happy to hold just 44% possession. Then again, very few would travel to Burnley with a five-man defence.

The best player on the pitch was Ciaran Clark, whose excellent glancing header won the match but who was even more influential at the other end. The 29-year-old amassed 11 clearances and won eight headers, both season highs for the former Aston Villa man. He also completed more passes (42) and more key passes (two) than in any other game this season.

Worst of the Week – Wolves' defensiveness

Huddersfield Town have been unlucky not to win more points this season, having hit the woodwork on numerous occasions and often dominating midfield; the return of Philip Billing has created a powerful and technically gifted central midfield, which should ensure the Terriers battle for survival right until the end of the campaign.

However, their improving form is no excuse for Wolves' negativity at Molineaux on Sunday. Nuno Esperito Santo's team have now gone five Premier League games without victory, the manager's consistent team selection and shape making Wolves look bereft of ideas. It was notably how quickly they dropped off, how infrequently they committed men forward, and how often the back three became a back five. Low confidence often leads to nervy, conservative performances – the exact opposite of what Wolves need to end this bad run of form.