Manchester United’s 0-0 draw with Cambridge United of League 2 was the latest in a string of disappointing performances which have plagued Louis van Gaal’s team since the Christmas period. Fans are outwardly displaying their discontent at Van Gaal’s use of a 5-3-2 formation with the players still not looking entirely comfortable in the new system.

There is the suggestion that Van Gaal is still not fully aware of what is his optimum lineup, with the Dutch coach himself citing the lack of time in pre-season to get to know his players is hampering results now. With this in mind, what would United’s best lineup be without any additions in the transfer market?

Manchester United supporters will tell you that the best period of this season came when Van Gaal utilized a 4-4-2 diamond system. The system totally freed the fantastic attacking talents of Angel Di Maria, Juan Mata and Wayne Rooney with even a not yet fully fit Radamel Falcao enjoying the vast amounts of creative service he received.

Of course there was a problem with this system, balance. Due to United’s lack of confidence and quality in defense the use of one sole holding midfielder in Daley Blind provided little protection for United’s struggling back line. United could quite easily create and convert chances but often David de Gea’s brilliance alone would keep United in the lead in matches.

United fans brought up on the lightning quick, zippy soccer of Sir Alex Ferguson were truly in their element during this part of the season, however it wasn’t a sustainable model with United’s defense under so much pressure. Van Gaal wanted his teams to control and dominate matches for large periods, and understandably so.

Injuries to Blind and Falcao then saw Van Gaal look for a system with even more balance to help out his ailing defense. The result was a 4-5-1 system which saw United win six straight Premier League matches including 2-1 and 3-0 victories against Arsenal and Liverpool respectively.

The introduction of Marouane Fellaini was the key element. The Belgian added a level of physicality to United’s play that had been missing in the opening stages of the season. United weren’t being bullied in midfield anymore and the attacking players had slightly more freedom to play. United were also helped by the fantastic form of Ashley Young at left-back during Luke Shaw’s absence with the former Villa man being integral to the new system.

Make no mistake, United weren’t as blisteringly brilliant going forward as with the 4-4-2 diamond, however, there was greater team strength, matches were being won at a canter and the club looked set for a return to the famous top four in third place.

Van Gaal is still lacking players in certain positions to really build a dominant team, but of course this process does take a bit of time, just ask Jose Mourinho at Chelsea last season, although he didn’t spend nearly the amount of money United did last summer. However, such was the scale of rebuilding needed at Old Trafford following years of transfer market complacency.

There is the feeling that Van Gaal would love to set up in a 4-4-2 diamond each week and have his stars rip teams to shreds and the addition of a world class centre-half and a very powerful box-to-box midfielder would prevent pressure from building on his defense. The system would then be balanced and sustainable, however, his two main targets, Mats Hummels and Kevin Strootman are not available until at least the summer.

Until then I feel the best line-up United have is the 4-5-1 simply because it has balance and it is proven to work.

It keeps pressure off United’s defense through the inclusion of Michael Carrick and Marouane Fellaini in central midfield whilst there are the attacking talents of Di Maria, Rooney, Ander Herrera and Robin Van Persie all present.

With United struggling for form and confidence at this point it is a remarkably similar situation to the one the club found themselves in just after the defeat at Manchester City and prior to the six match winning run. United need to build momentum yet again and the 4-5-1 is probably the best option in doing so.