Manchester United will have to pay ­£15million including add-ons AND allow ­Wilfried Zaha to stay at Selhurst Park for the rest of the season to sign the Crystal Palace whizz-kid.

Sir Alex Ferguson has been making his own checks on Zaha (above) and his personal ­intervention in the process suggests that United are ready to increase their initial bid of £10m.

The United boss has spoken to a number of people who know the 20-year-old winger both professionally and personally.

And the message back was that Zaha has the mental attitude as well as the technical aptitude to be a success at Old Trafford.

Surplus to requirements: Nani is the player likely to give way to Zaha (
Image:
Clive Rose)

Palace boss Ian Holloway is desperate not to lose his most prized asset with the Eagles pushing for promotion to the Premier League.

He accepts that a move to United is impossible to resist, but the key to any deal would be a willingness from United to allow Zaha to stay with Palace for the remainder of the campaign.

Ferguson already has Antonio Valencia, Ashley Young and Nani in his squad.

Nani is the likely candidate to be sacrificed if a deal for Zaha is sealed, although Ferguson will wait until the end of the season before selling if Zaha stays in London until the summer.

The United boss has been monitoring Zaha’s development since he produced an outstanding performance when Palace knocked United out of the League Cup last season.