Mikel Arteta has returned to Arsenal as the club's new head coach.

The former midfielder spent five years at the Emirates Stadium before retiring in 2016 and has spent the last three years under the tutelage of Manchester City boss Pep Guardiola as his assistant coach.

But the 37-year-old has been given the opportunity to make his mark in management after signing a three-and-a-half-year deal as Unai Emery's permanent successor.

Here, the PA news agency looks at some of the issues the Spaniard will have to deal with at Arsenal.

A case for the defence

One of Arsenal's weaknesses for over a decade has been their defence but long-serving manager Arsene Wenger and Emery failed to deal with the obvious flaws, which has seen the club fall from title challengers to struggling in their fight for a top-six finish in the Premier League. The recruitment of centre-backs Sokratis Papastathopoulos and David Luiz in recent seasons have only exacerbated the problem and Arteta needs to get a grip on the backline before he can start working on improving further up the field.

Style or substance?

Arsenal fans were spoilt during Wenger's 22-year reign when he brought silverware by playing attractive football. His style of play remained intact, which pleased the Gunners faithful, but the fanbase grew tired of a lacking title challenge towards the latter stages of his tenure. However, under Emery the attacking style faded as did the results, so the question for Arteta is does he want instant results – which the club desperately needs – or does he push for his brand of football which may prolong those results from happening?

Find a system and stick with it

Emery's demise at the Emirates was due to a lack of tactical stability throughout his stay. He constantly tinkered with different varieties of a back-four formation before changing to a three-man defence, only to swiftly revert back to his initial plan. Interim boss Freddie Ljungberg fell victim to this during his five-match spell in caretaker charge and it would be clearer to the players and fans if they stuck to one system which they can try to perfect, ideally with Pierre-Emerick Aubameyang and Alexandre Lacazette playing together in attack.

Install a winning mentality

Under Guardiola, Arteta has been part of the coaching staff with two Premier League-winning teams which also included City's historic domestic clean sweep last season. The Spaniard won two FA Cups during his time as a player at Arsenal and could provide some leadership which has been desperately lacking for a long time at the Gunners, both on and off the field. Arsenal reached the Europa League final in May under Emery but fell to a crushing 4-1 defeat to Chelsea, extending Arsenal's trophy drought to three years. Arteta inherits a team which has won just once in their last 12 matches in all competitions.

Sort the Mesut Ozil conundrum

Everyone can see the ability that the former Germany international possesses but he has not shown that on a consistent basis, especially since signing his mega three-and-a-half year deal in January 2018. Wenger loved him but Emery used him sparingly, so Arteta will have a decision to make. The Spaniard will either have to build a team around his former team-mate, or get him off the wage bill to get in players that he wants. Ozil's meltdown during the 3-0 home defeat to City on December 15, when he kicked his gloves as he was substituted in the 59th minute – in front of Arteta in the opposition dugout – will not have gone unnoticed either.

Get full potential out of players

One positive during Emery's reign was the amount of academy players who broke into the first-team picture. The likes of Joe Willock, Reiss Nelson, Emile Smith Rowe and more recently Bukayo Saka have had valuable minutes over the last 12 months but none have secured regular starting positions. Brazilian youngster Gabriel Martinelli has also looked promising during his first season at the club and if Arteta can get a tune out of Lucas Torreira and Nicolas Pepe, Arsenal do have a squad capable of competing for trophies – provided he is given money to improve his options.