Manchester City moved within four points of Liverpool on Thursday night to reignite the Premier League title race, ending the visitors' unbeaten season in the process. That was the big result of the midweek round, although Southampton's 0-0 draw with Chelsea was equally important at the other end of the table.
Here are three tactical things we learnt from the week's action:
1) Liverpool's inability to work around Man City's press leads to defeat
Man City's defensive block was outstanding, but Liverpool's midfield could have worked harder to make space as their own defenders tried (and largely failed) to work around City and build an attack. Jordan Henderson didn't do enough to come short, while the front three were too disconnected, expecting their team-mates to outmanoeuvre City rather than showing for the ball.
Liverpool could have benefitted from playing longer diagonals over the top of the City midfield, but rarely did Sadio Mane or Mohamed Salah seek this option – that is until the final 25 minutes when Fabinho's introduction changed the game. Liverpool's equaliser came from Mane finally coming short – and narrow – to dribble around a City player and open up the pitch. Three long switches of play later and the ball was in the back of the net. It was a tactic they should have been attempting from the first whistle.
2) Southampton's "good mixture" of defending cancels out Chelsea
Ralph Hasenhuttl's tactical coaching is starting to take effect. As we highlighted in our in-depth tactical report from Stamford Bridge, his team superbly switched between a 3-4-2-1 and 5-4-1 throughout the game, the latter allowing them to triple up on Eden Hazard and the former seeing the wing-backs push forward and the whole team press aggressively in the Chelsea half.
The hosts were never able to settle, with Southampton showing fierce energy in closing down their opponents. This caused nervousness and ensured the visitors could break forward on occasion rather than sit deep and await the Chelsea opener. After the game Hasenhuttl described it as a "good mix" of pressing and standing off; it takes complex positional coaching to shift between two distinct defensive styles, which is why Saints fans can be hopeful of Hasenhuttl getting them out of the bottom three sooner rather than later.
3) Strange Arsenal first half shows why life without Ozil and Ramsey will be tough
Arsenal might have run out 4-1 winners at the Emirates but it was a very odd performance from Unai Emery's side, who deployed a flat 3-4-3 formation that left the Gunners without any players in the number ten space – despite the fact this is Fulham's weakest area. Inevitably, Arsenal persistently pushed down the flanks and Fulham largely mopped up safely; it was a reminder that life may be tough for Emery without Mesut Ozil and Aaron Ramsey next season.
In the second half Fulham changed to a 4-4-2 with Aboubakar Kamara's pace causing problems as Claudio Ranieri went more direct. But Emery made made his own switch - to a 4-3-3 at half-time – that ultimately wrestled control of the midfield and led to a flurry of second half goals. However, better opposition than Fulham would have taken advantage of a flat, static first half from three Arsenal forwards crying out for an Ozil-shaped link between them and the midfield.
Best of the Week – Fernandinho & Bernardo Silva
Among a near perfect defensive display from the entire team, two players stood out in particular at the Etihad. Fernandinho's commanding defensive display and control of possession accentuated Henderson's issues from the same position, the Brazilian ensuring Liverpool's forwards had no space on the rare occasion that the ball broke beyond the first line of the City press.
Bernardo Silva was just as good, his movement and work-rate setting the tone from the front. The Portuguese finished the match with three tackles and four interceptions, more than any other player on the pitch.
Worst of the Week – Huddersfield's collapse
We all know that Huddersfield have struggled to score goals this season, but judging by Wednesday's collapse their defending can be just as poor; losing to Burnley in that manner suggests David Wagner's side have no chance of staying up.
The first goal was terrible defending from Florent Hadergjonaj as he was turned inside out, while the second saw Ashley Barnes easily split the centre-backs – something you very rarely see from a Burnley player in the Premier League.