Arsenal's well deserved victory over Chelsea at the Emirates on Saturday could prove to be a huge result and performance for three Premier League sides. The hosts appear to have finally found the right formation to maximise their talents, Chelsea reached breaking point with Maurizio Sarri laying into his players after the match, and Manchester United moved within three points of the top four.

There weren't too many other stories developing over the weekend, although a couple of 4-3s livened up Match of the Day on a Saturday in which, across eight games, only one point was won by the away teams.

Here are three things we learnt from the weekend Premier League football:

1) Ramsey's performance in defence and attack suggests Arsenal's future is in a diamond 4-4-2

Unai Emery sprang another surprise on Saturday by playing a diamond 4-4-2 formation for the first time, and given Arsenal's success at the Emirates we could see this system feature regularly in the coming months. For a while now Arsenal have lacked rhythm due to the ineffectiveness of both Alexandre Lacazette and Pierre-Emerick Aubameyang outside the box, but as strikers in this new system they are only needed on the shoulder of the last defender.

That's because Arsenal have four central midfielders on the pitch, allowing them to control the match and push the defenders back (the threat of the forwards certainly caused nervousness in the Chelsea defence). The biggest change has been getting the most out of Aaron Ramsey, who excelled in the number ten role both offensively and defensively.

Ramsey sat on top of Jorginho when Chelsea had possession, stunting the visitors' influence and ensuring Arsenal remained firmly in charge of the game. What's more, Matteo Guendouzi and Lucas Torreira were surprisingly efficient as wide midfielders, supporting the flanks well enough to allow Hector Bellerin and Sead Kolasinac to get forward.

It looks as though Emery has finally found the formation to focus on until the end of the season.

2) Milner's poor defending highlights the importance of Liverpool's full-backs

The nature of Liverpool's aggressive high defensive line means they need pace and agility across the back four, something highlighted in Trent Alexander-Arnold's absence by James Milner's poor performance in Liverpool's 4-3 victory over Crystal Palace. The match rightly drew comparisons with the chaotic Liverpool of 2017/18, when Milner regularly played at full-back.

Andros Townsend gave the visitors the lead after Wilfried Zaha turned Milner inside out on the left to expose his creaking limbs. Milner then lunged into tackles several times in the first half, further destabilising the defence and eventually leading to Palace's second goal (his missed tackle allowed Palace to counter down the left, winning a corner from which James Tomkins scored).

Milner's sluggishness was perhaps most evident in his two badly mistimed tackles that led to his dismissal: both could have been given as straight reds; both betrayed his inability to keep up with the pace of the game.

3) Harry Winks provides engine in midfield to help Spurs break down Fulham

Had Fernando Llorente performed better than Spurs would have comfortably beaten Fulham at Craven Cottage, but instead it took a last-minute header from the best player on the pitch – Harry Winks – to win the three points. He was the engine in midfield, attempting 102 passes, more than any other player on the pitch and a season high for Winks.

Spurs didn't create many chances, primarily because Erik Lamela and Dele Alli were so narrow that Danny Rose and Kieran Trippier were halted in one-on-ones on the flanks, but nevertheless Winks recycled possession well and kept probing. His energy in making that late run into the six-yard box typified a hungry performance that, at a time when Mauricio Pochettino is struggling with injuries, showed real leadership.

Best of the Week – Ruben Neves

Ruben Neves was once again the dominant force behind a Wolves win at the weekend, playing 12 long balls that helped shift his team through the gears and counter-attack behind a prosaic Leicester City team.

He earned an assist for the third goal with a lovely ball through to Diogo Jota, before another excellent through pass provided the pre-assist for the fourth. It was his long-range shot, finger-tipped over the bar, that earned the corner for Wolves' fourth minute opener.

Worst of the Week – Chelsea's stale attack

Chelsea have now scored just 13 goals in their last 12 league games and Maurizio Sarri deserves criticism for his stubbornness. They are far too predictable, using the same formation and line-up for every match, and that's why opponents have learnt how to nullify Sarri-ball; man-mark Jorginho and double up on Eden Hazard, and it's fairly easy to keep a clean sheet.

Sarri bemoaned his side's motivation after the game, and yet in reality it is a lack of variation that has caused their positional play to lose its fluidity. Perhaps Gonzalo Higuain's arrival will shake things up.