Higuain underwent an operation on his back injury in Chicago on Tuesday and the doctor who performed the surgery confirmed afterwards the Argentina international would be absent for between three and four months.

That would mean Higuain is unlikely to be available again until the final weeks of the season and would leave Madrid coach Jose Mourinho with just Karim Benzema as his only senior centre-forward.

Madrid had appeared reluctant to bring in a new striker but Valdano admitted tonight they are looking at options.

"We are exploring the market now the uncertainty around Higuain has been resolved. We'll see if we can find a player who can help us for six months," said Valdano following Madrid's 3-1 Copa del Rey quarter-final first leg win over local rivals Atletico.

Numerous strikers have been linked with the Spanish giants, including Miroslav Klose, Emmanuel Adebayor and Nelson Haedo Valdez, but Valdano preferred not to comment on possible targets.

"Many names are being mentioned and it's best not to go into details. But it's true we are looking for a number nine," he said in AS.