In terms of selection headaches, choosing between David de Gea and Anders Lindegaard is perhaps the one that Sir Alex Ferguson faces going into each match.

It is the first time Manchester United have not had a stable number one since the period between 2003 and 2005; when Ferguson could not decide between Tim Howard and Roy Carroll.

De Gea is seemingly preferred for the European and Cup matches where his great shot-stopping skills come to the fore, whereas Lindegaard has featured more often in the Premier League and is better at dealing with high balls into the area.

The issue of not having an established number one does not seem to bother the United manager, who says that he will continue to rotate his goalkeepers as they both have time to prove themselves.

The argument is a sound one, with De Gea, 21 and Lindegaard, 28-years-old respectively.

Ferguson has pointed to the fact that Peter Schmeichel was 27 when he joined the club and had eight highly successful years at the club.

But surely rotating between goalkeepers has an unsettling effect on the defence?

The likes of Rio Ferdinand and Johnny Evans would probably prefer to have a consistent number one playing behind them; and need to be regularly accustomed to one particular goalkeeper.

It could explain United’s defensively shaky start to the season, with a different goalkeeper likely to add to the level of uncertainty at the back.

De Gea and Lindegaard are both equally capable of playing at the top level; and the fact that neither goalkeeper has nailed down the first-choice berth is due to their different qualities between the posts.

De Gea is prone to an error or two, but he must be praised for the way he turned around his personal fortunes last season, quickly realising he needed to be physically stronger to adapt to the Premier League.

His shot-stopping is superb and can be relied upon to make vital saves at crucial times, but still looks susceptible to long balls and high crosses into the area- meaning he is not yet the finished article.

This has caused Ferguson to doubt whether the goalkeeper can perform consistently week-in-out; an issue that cannot be raised with De Gea’s Danish teammate.

Lindegaard has been reliable when called upon and does not seem to suffer the same pressure as De Gea.

He arrived at the club for a far smaller fee, £3.5 million as opposed to the £17million paid for De Gea; and seems to be far more assured in dealing with those dreaded high balls into the box that the Spaniard is still fazed by.

But unlike De Gea, Lindegaard has seemingly reached the pinnacle of his potential and is likely to stand down for the 21-year-old in the near future.

If De Gea continues to work on the chinks in his armour with United’s coaching staff then he could be one of the world’s best keepers in years to come, but he needs an extended run in the team.

In order to accelerate his development, it may be time once and for all to thrust the Spaniard back into the number one sport and see how he deals with the pressure, at the expense of Lindegaard.

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