Premier League: What to look out for this season

Do Virgil van Dijk, Timo Werner and Ole Gunnar Solskjaer all have a point to prove?

What are Manchester City's chances of defending the title? Which players have a point to prove? Who are the managers feeling the heat? There are plenty of questions to be answered in the Premier League this season.

The new campaign starts on Friday when Arsenal take on newcomers Brentford.

BBC Sport takes a look at some of the subplots to watch for.

Man City to defend their title?

Pep Guardiola won his third Premier League title in four seasons with Manchester City

The Premier League begins its 30th season with Manchester City heading into the campaign as champions, but they have a sizeable task on their hands to retain the trophy.

Pep Guardiola's side were in imperious form as they went 28 games without defeat in all competitions - which included a remarkable 21-match winning streak - to win the title by 12 points over Manchester United.

But only three teams on six previous occasions have managed to defend their crown the following season. Manchester United and Chelsea have done it, while City were the most recent team to achieve the feat with success in 2017-18 and 2018-19.

Guardiola told BBC Sport in May: "In the previous season, Liverpool were unstoppable and everyone believed it would be the same again, but that is a good lesson for us.

"Nothing is taken for granted. We can have injuries, have bad moments and that is why the warnings always have to be on."

City have strengthened an attacking line-up that is already overflowing with talent by bringing in England international Jack Grealish for a British record £100m, while they could break that fee again if they complete a deal for Tottenham striker Harry Kane.

But other title challengers have strengthened too, Manchester United have signed Jadon Sancho and Raphael Varane to reinforce their right wing and defence.

Players with a point to prove

Timo Werner scored just six league goals last season

The summer signings will be hoping they don't flop for their new teams, but there are a few Premier League old boys that might have a point to prove this season.

Look no further than Chelsea forward Timo Werner.

Signed from RB Leipzig for £47m last June, Werner lifted the Champions League trophy with the Blues, but had a substandard time in front of goal.

Werner scored 12 goals throughout the whole campaign, just six in the league, and went on one run of 13 games without finding the net for club and country, followed by another of 14 matches.

Staying in London, Arsenal captain Pierre-Emerick Aubameyang will be hoping for a better campaign after the Gunners finished eighth in the table, missing out on European football for the first time in 25 years.

Aubameyang himself had plenty of problems to deal with - absent from the side in January as his mother was ill, dropped for the win over Tottenham in March because of a "disciplinary issue" and losing four kilos in weight after contracting malaria on international duty in March.

Leeds striker Patrick Bamford impressed on their return to the top flight by netting 17 league goals, but it was not enough for a place in England's 26-man squad for the Euros.

Bamford will be aiming to continue that fine form into the new campaign to remind Gareth Southgate of his abilities, but still has room for improvement having missed 21 'big chances' last term - the most of any Premier League player.

Two stars who suffered injury problems will be keen to showcase their best once more. Leicester's James Maddison struggled after missing two months with a hip problem while Liverpool centre-back Virgil van Dijk returns to action after nine months out with a knee injury.

Managers feeling the heat

There are some on the sidelines that need to impress too.

Ole Gunnar Solskjaer signed a new deal with Manchester United until 2024, but will be under pressure to get off to a fast start and deliver a trophy at the end of the season having lost last year's Europa League final against Villarreal.

Arsenal boss Mikel Arteta started his managerial career in perfect fashion by winning the FA Cup, but his side have fared rather badly since and the Spaniard will need to improve on last season's finish.

What sort of reception will former Liverpool boss Rafael Benitez receive after his controversial move to become manager of Merseyside rivals Everton?

Benitez once called the Toffees a "small club", while several banners were hung outside Goodison Park protesting at the club's move for the Spaniard.

The Afcon factor

Algeria, captained by Manchester City's Riyad Mahrez, won the Africa Cup of Nations in 2019

The turn of the new year sees the staging of the Africa Cup of Nations (Afcon), taking place from 9 January to 6 February in Cameroon.

Some clubs could lose key players during a busy period for English clubs.

Liverpool may be the hardest hit as Egypt and Senegal have both qualified - meaning the Reds may lose attacking duo Mohamed Salah and Sadio Mane, as well as Guinea midfielder Naby Keita.

There are likely to be call-ups too for Chelsea keeper Edouard Mendy, Watford's star forward Ismaila Sarr (both Senegal), Manchester City's Riyad Mahrez and West Ham's Said Benrahma (both Algeria), Arsenal duo Aubameyang (Gabon) and Thomas Partey (Ghana), as well as Leicester's Wilfred Ndidi (Nigeria).

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