Although Los Merengues have a stunning array of attacking talent, their lack of defensive cover proved their downfall this season - seeing them end the campaign trophyless.
Real failed to properly replace Fernando Hierro after his departure last summer, and Valdano feels the arrival of Argentine international Samuel from Roma will finally give them the defensive power they have been lacking.
"His signing will balance the squad so we don't have the problems we've had recently," Valdano told Real Madrid TV.
"We are aware of our necessities and we are now trying to fill them so that next season we have more cover in all areas and a deeper squad that will allow us to survive in all competitions and get to the final two months with the chance to finally win a Cup."
On Samuel, Valdano continued: "He is a natural defender.
"He has a lot of talent when he does have the ball, a good sense of anticipation, is able to use his body and is powerful and strong in the air.
"He is a defender the like of whom are very few in Spain."
