sir alex ferguson
Sir Alex Ferguson has often cut a forlorn figure in the Old Trafford stands this season.(Reuters)

It was clear when Sir Alex Ferguson announced he would be retiring at the end of last season that whoever took over was going to have huge boots to fill. The appointment of David Moyes as the new manager was a popular one with the fans as he was recommended by the former boss himself and had done an admirable job at Everton.

However, with United languishing in seventh place in the Premier League, Moyes' first few months have been a huge disappointment, despite the glimmer of light provided by victory over Olympiakos in the Champions League.

But how much of the blame should be placed with Moyes and how much should be placed on the man who has told the world he recommended him for the job?

Well, first and foremost, it's important to point out that winning the Premier League last season by a massive 11 points from rivals Manchester City may well have been Ferguson's greatest achievement during his 27 years at the club. His squad was certainly not the best in the league but the signing of Robin van Persie proved the difference as he scored 26 goals in the Premier League to give United their unprecedented 20th title.

When van Persie is injured, the United squad certainly lacks the depth that the likes of Manchester City and Chelsea have available to them. This can be clearly seen in the signings Ferguson made in his last couple of seasons at the club. With the exception of the Dutch striker, the only players he brought into the club were Shinji Kagawa, Wilfried Zaha, Alex Buttner and David de Gea. Of these the only player who has secured an automatic first-team place is De Gea.

Compare this minimal outlay on players to those Ferguson let go, and a disproportionate picture emerges. With the likes of Paul Pogba, Ji-Sung Park, Dimitar Berbatov, John O'Shea, Wes Brown, Owen Hargreaves and Darron Gibson all leaving the club, along with the retirement of Paul Scholes, more signings needed to be made. Moyes discovered the lack of depth in the squad when taking over this past summer.

Admittedly, he was far too slow in the transfer market and spent far too long chasing the likes of Cesc Fabregas instead of focusing on multiple targets and securing deals early on. The signing of Marouane Fellaini looks to be an expensive one and it remains to be seen where Juan Mata fits into the squad. However, the six-year contract Moyes signed signals the intentions of the backroom staff at United, and the win against Olympiacos to take the team through to the Champions League quarter finals will decrease any pressure on him temporarily.

The challenge Moyes faces is trying to improve the squad this summer as well as deciding the style of play he wishes to move forward with. Traditionally United have always been a team who play with fast wingers and rely on crossing the ball. Simply put, the club do not have the players to play this way at present, and when looking across Europe the vast majority of clubs now have two or three ways they can approach a game.

The niche way of playing which United fans enjoyed under Ferguson may have to be sacrificed if Moyes is to prove himself as a top manager who can win major honours with the club. What is clear is he was not helped by the lack of depth in the squad which he inherited from Sir Alex Ferguson.

Luke Gardener is a lifelong Manchester United fan and a regular writer on the club. You can follow him @LukeGardener82.

The article was kindly provided by Man United World, one of the biggest United fan resources on the web. You can read more of their articles at  TalkingUnited.com or follow them @ManUnitedWorld.