As Louis van Gaal trudged off the pitch following Manchester United’s 2-1 humbling by Norwich, the sounds of supporters’ discontent will have been ringing in his ears.

Pressure is mounting on the Dutchman in his second season in charge – with players still struggling to buy into his so-called ‘philosophy’ while results have slumped on par with David Moyes’ ill-fated reign at Old Trafford.

Should the United board decide to make a change, Sportsmail looks at the pros and cons of the three leading contenders to take over the United hotseat… 

Louis van Gaal looks towards the stands as he trudges off the pitch to sounds of discontent at Old Trafford

David de Gea slumps to the floor after conceding as United’s winless run is stretched to six games

CONTENDER NO 1: JOSE MOURINHO

After being sacked as Chelsea manager on Thursday, Jose Mourinho could yet realise his dream of managing Manchester United.

Jose Mourinho is likely to return silverware, but there are doubts over whether he has the right attitude

PROS:

• Mourinho is immediately available for work after being dismissed from Stamford Bridge  for the by Roman Abamovich following the worst title defence in Premier League history.
• He is one of the most successful managers in football history having won silverware at almost every club he has managed, including a pair of Champions League titles – with Porto and Inter Milan.
• The Portuguese has delivered trophies in each of the four different leagues – Portugal, England, Italy and Spain – he has managed and United are used to having a fully stocked trophy cabinet.

It may not have ended well for Mourinho at Stamford Bridge, but his arrival is usually followed by silverware

CONS:

• Mourinho is hardly the stable and assured character that Manchester United would like, which may be the reason that David Moyes was preferred to him in the first instance.
• If United fans consider Van Gaal’s style of football boring, Mourinho’s brand of play is equally unlikely to excite them. Mourinho prefers to take a pragmatic approach based on defensive foundations.
• It has been argued that Mourinho has a three-year shelf life, which usually includes a glorious beginning truncated by an acrimonious end, which will not fit into United’s long-term plan. 

CONTENDER NO 2: PEP GUARDIOLA 

Having confirmed that he will leave Bayern Munich at the end of the season, Pep Guardiola’s pedigree and football philosophy are a perfect match for United.  

Pep Guardiola’s pedigree and football philosophy are tailor made for Manchester United 

PROS: 

• Guardiola’s experience as both a player and manager have made him the most sought after manager in the world after he announced he is on the market.
• Unlike Van Gaal and Mourinho, Guardiola’s schooling at Barcelona means he preaches a brand of attacking football that Manchester United fans have been craving since Sir Alex Ferguson retired.
• The Spaniard has brought the best out of some of the best players in the history of the game, including arguably the world’s greatest player Lionel Messi and reinventing Philipp Lahm.

Guardiola is the most sought after coach in the world, although City may have already beat United to the chase

CONS: 

• As the world’s most wanted manager, clubs including Chelsea and Manchester City are also in the chase for the Spaniard – with reports from Germany suggesting he has already decided to join his former Barca associates at the Emirates.
• He has only ever taken charge of established teams bursting with talent, while the weaknesses in United’s current squad have been well documented despite the millions spent under Van Gaal.
• Like Mourinho, Guardiola may not be interested in staying at one club for the long-term – while United would prefer a manager to build a legacy in the mould of Ferguson before them.

CONTENDER NO 3: RYAN GIGGS 

As Manchester United’s most decorated player, Ryan Giggs has been learning the managerial ropes under Van Gaal and stepping up would be popular with the fans.

Ryan Giggs would be a popular choice to escape Van Gaal’s shackles and return United’s attacking verve

PROS:

• Having spent his entire playing career at Old Trafford before seamlessly stepping into coach, no other contender knows the club as well as Giggs – and he is desperate to take the job.
• While his school under Van Gaal may have been frustrating, Giggs has played for and learned from the most successful manager in Manchester United’s history – one Sir Alex Ferguson.
• As his pitchside expressions sometimes portray, Giggs understands the fans and seems to yearn for a more adventurous style of play in keeping with his own flair as a player.

No other contender knows the fans and understands the club as well as United legend Giggs

CONS:

• Although he temporarily took control of the team in the wake of David Moyes’ departure, the Welshman is hugely inexperienced at this or any level – United would be his first job in management.
• While he advocated United’s traditional attacking principles, Giggs’ spell as caretaker manager was less than impressive with two wins from the four games he managed.
• There is a fear that one of the biggest jobs in world football could come too soon for Giggs, while failure could scar his future as a manager and tarnish his reputation at Old Trafford.