1. Firmino joins the 20 club to show why Klopp always had faith in him.

It has been a weekend for Liverpool players past and present to prove they are more prolific than many thought possible. On Saturday, Raheem Sterling reached the 20-goal landmark for the first time in a season. The following day, Roberto Firmino reached the milestone for the first time in England. Rewind to last week and one of the more finer finishers in Liverpool’s history, John Aldridge, said they needed a 25-30 goal-a-season striker. He may not have noticed but they have one. There are three months of the campaign to go and Firmino is on course for 30.

AS IT HAPPENED: Southampton vs Liverpool

READ MORE: Firmino and Salah move Reds to within two points of Man Utd

But, unlike some specialist predators, the Brazilian allies an increasingly clinical touch with much else: an incessant work rate to enable him to lead the pressing game and the skill to execute a cute backheel that allowed Mohamed Salah to score Liverpool’s second goal, for instance.

He has not reduced his efforts for his colleagues to become a better goalscorer. He has simply improved in a way to justify Jurgen Klopp’s decision to install him as the first-choice forward long before his goal-return was as good. Because, even before Daniel Sturridge left Anfield on loan, Firmino had ended the debate about who should lead the line for Liverpool. And had Salah not scored quite as many goals, his own exploits would have garnered more attention.

2. Smalling’s hapless display costs Manchester United in Newcastle.

The temptation is to focus on Paul Pogba. For the second consecutive away game, he was a reason why Manchester United lost. Once again, he was substituted early. If he failed to occupy the right position against Tottenham, when he left his defence exposed, he failed to cover enough ground against Newcastle, seemingly hampered by a problem he sustained in the warm up. Symbolically, he failed to jump for a header in the build-up to Matt Ritchie’s goal and was removed right away.

AS IT HAPPENED: Newcastle vs Man Utd

READ MORE: Ritchie strike keeps City 16 points clear

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And yet Pogba was not the most culpable man in red. That was Chris Smalling. He could be excused for his role in United’s disallowed goal, when he was penalised as he headed the ball into Romelu Lukaku’s path. He escaped with fouling Dwight Gayle in the penalty area. But an error-strewn display was compounded when he contrived to give away the free kick that led to the Newcastle winner; for diving, and in his own half.

The real punishment did not come in the form of the yellow card Craig Pawson brandished. This was an afternoon to offer a reminder that the injured Eric Bailly remains United’s best centre-back and that Smalling, whose decision-making can be faulty, is distinctly fortunate to have had an eight-season career at Old Trafford.

3. Davies’ improvement shows why Spurs have overhauled Arsenal.

If a Harry Kane winner in a north London derby would have felt predictable at almost any point in the last three years, his supplier on Saturday offered proof of Tottenham’s capacity to improve with their existing players. While Arsenal gave second starts for their new club to Pierre-Emerick Aubameyang and the ineffective Henrikh Mkhitaryan, Ben Davies delivered a superb cross that Harry Kane headed in for the only goal at Wembley.

Tottenham v Arsenal: How the match unfolded

READ MORE: Kane strikes as Spurs beat Arsenal at Wembley

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The Welshman used to be seen as an essentially defensive left-back, but that has changed. Once again, a player has developed beyond recognition under Mauricio Pochettino’s supervision. This was Davies’ fifth assist of the league season; Cesar Azpilicueta is the only defender with more. It also brought a comparison with the left-back Arsenal did sign in the summer: Sead Kolasinac looked an attacking force at times in his first few months but he has lost his place and went unused again.

They are individual tales but they help explain why Tottenham are the dominant force in north London now. And while Danny Rose is fit again now, Davies is playing so well he may be Spurs’ best option at left-back now.

4. Aguero gets more potent in Jesus’ absence.

It was New Year’s Eve when Gabriel Jesus was substituted in tears at Selhurst Park, a knee injury threatening to come at a serious cost to Manchester City. Instead, they have barely missed one of the world’s most exciting strikers. Since then, Sergio Aguero has scored 13 goals, including three against Newcastle and four on Saturday against Leicester. By way of comparison, Chelsea have only mustered 12 goals in 2018.

Manchester City v Leicester: How the match unfolded

READ MORE: De Bruyne inspires as Aguero scores four

READ MORE: Mahrez on the bench for Manchester City clash

The sense is that Aguero is relishing the responsibility of being City’s only fit striker. He is less likely to be substituted early, let alone start on the bench. He was relatively quiet in the first half against Leicester. He exploded in the second, first with a poacher’s finishes and then with the more memorable goals, a delicate chip and a thunderbolt.

The range in his repertoire explains why he has reached passed the 20-goal mark for a fourth consecutive Premier League season. He could become the first man to score 200 times for City, perhaps as early as Tuesday night against Basel, and better his season’s best tally of 33 goals. Not bad for a campaign when he has had a battle for his place.

5. Carvalhal helps history repeat itself at Swansea.

It may have seemed a strange job description. Carlos Carvalhal was hired by Swansea, charged with repeating the exploits of his sacked predecessor, who left the Welsh club bottom of the league. Or, to be more exact, charged with emulating the job Paul Clement did last season when he extricated Swansea from a similarly difficult predicament. Then the Swans only took 12 points from their first 19 games, transforming their campaign with a 29-point haul from the second half of the season.

Swansea v Burnley: How the match unfolded

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READ MORE: Swansea breathing fresh air and swimming for safety, Carvalhal proclaims

When Carvalhal brought an injection of energy, the situation was almost identical: Swansea had 13 points from 20 matches. So was the immediate impact. Saturday’s 1-0 win over Burnley took his haul to 14 points from seven games.

The Portuguese has made a difference with tactical changes, like using three centre-backs and deploying the energetic Jordan Ayew as his main striker. He has brought change with his substitutions, and Tammy Abraham made a difference against Burnley. Above all, he has effected a mood swing. From being doomed, Swansea are now on course to survive.