Five observations from the weekend's Premier League action

Manchester United star Paul Pogba is still struggling, but Swansea are on the up under Carlos Carvalhal.

Here are five things we learned from the Premier League this weekend:

- De Bruyne steps up - 

Sergio Aguero grabbed the headlines for his four-goal second-half haul as Manchester City leaped another step closer to Pep Guardiola's first Premier League title in a 5-1 thrashing of Leicester, but it was Kevin De Bruyne who was once again the architect of City's success. The Belgian even momentarily joked he, not Aguero, was having the match ball for a hat-trick of assists for Raheem Sterling's opener and Aguero's first two goals. "He has everything," gushed Guardiola. "Every game... amount of assists, amount of passes, shots, goals, how he fights, how he runs... this season the performance of Kevin so far there are no words. It's so special." De Bruyne's display was even more inspirational as he took responsibility given City's current lack of cover in creative areas in the absence of David Silva and Leroy Sane through injury.

- Dembele the midfield maestro - 

Mousa Dembele underlined his status as one of Tottenham's unsung heroes with a dominant display in their 1-0 win over north London rivals Arsenal. It was Harry Kane's latest goal-scoring exploits against the Gunners that took centre-stage at Wembley, but the platform of that success was built by the industrious Dembele. Embodying Mauricio Pochettino's obsession with physical intensity, while more than capable of picking a decisive pass, Dembele out-shone Arsenal in the midfield engine room, earning praise from his manager. "Last season he played so well, this season he suffered a problem in his ankle and struggled in pre-season. Now he is playing well again," Pochettino said. "He is an unbelievable player. We have to be careful about his fitness. When he can train he can make this type of performance."

- Pogba flops again - 

As if losing 1-0 to struggling Newcastle wasn't enough to have Jose Mourinho seething, the Manchester United boss once again had to suffer the frustration of Paul Pogba's latest flop. Mourinho had restored Pogba to the starting line-up after dropping him for United's previous match -- a decision inspired by the former Juventus midfielder's limp efforts in a defeat at Tottenham. But rather than grasp the opportunity to get back in Mourinho's good books just days after his boss had defended their relationship, Pogba was again a largely anonymous figure at St James' Park. By the time he was substituted midway through the second half, United were already trailing, but publicly at least, Mourinho remains supportive. "No problems," he said when asked about the France international. "I wanted a better way (in midfield) against a side that was defending in a block. I wanted the simplicity of Michael Carrick."

- Carvalhal has Swansea cooking -

Carlos Carvalhal has served up amazing results and interviews in equal measure since he was surprisingly appointed to spearhead Swansea's fight for survival on December 28. Saturday was no different as Ki Sung-Yeung's winner nine minutes from time after Carvalhal had thrown on two extra strikers took the Welsh side out of the relegation zone. When the Portuguese arrived, Swansea were bottom of the table and five points adrift of safety. "It was time to put all the meat on the barbeque," said the colourful Carvalhal of his attacking instinct. Swansea have now won more points, 14, in Carvalhal's seven games in charge than the 13 his predecessor Paul Clement collected in 20 matches.

- Southampton slide into bottom three - 

Whilst Huddersfield, Newcastle and Swansea enjoyed morale-boosting wins, Southampton's slide continued as Mauricio Pellegrino's men were swept aside 2-0 by Liverpool. A run of just one win in their last 14 league outings has seen the Saints slip into the bottom three. An unwillingness to spend the £75 million bounty they received from Virgil van Dijk's move to Liverpool in January could come back to cost the Southampton hierarchy as they look short of inspiration in attack and are badly missing the Dutchman in defence.