Manchester United have received a boost in their hopes to keep David De Gea at Old Trafford after reports in Spain revealed Real Madrid are considering to sign Bayer Leverkusen goalkeeper Bernd Leno as a cheaper alternative to replace Iker Casillas.

The Champions League winners have been preparing for life without their current number one for a while as he is expected to put an end to his spell at Santiago Bernabeu, either at the end of the campaign or the following summer.

The 24-year-old United keeper is said to be their top priority to fill the void, but Spanish newspaper Marca reports that they are also considering other options should the Spaniard finally opt to stay at Old Trafford.

Marca claims that Real Madrid have indeed been tracking the German under 21 international since the beginning of the year and their scouts have been so impressed by his skills they believe he has the potential to be as good as De Gea himself.

The reports insist that De Gea remains as Real Madrid's main choice to replace Casillas but the Spanish giants are considering the Bayer Leverkusen starlet as a cheaper alternative, as his release clause at the Bundesliga side is just €18m (£13, $19.4m) while the negotiations with the German club would be easier than with United.

Nevertheless, Marca insist that De Gea is yet to make a final decision about whether to commit his future to Old Trafford with a new deal as his current one is due to expire in summer 2016.

According to the report, De Gea's agent Jorge Mendes was at Old Trafford last week, but the deal is still off as the United keeper is awaiting to know the future of Casillas at the Santiago Bernabeu before making a final decision.