The Blancos are faced with selection crisis ahead of the second leg of their semi-final fixture against Bavarians after Dani Carvajal suffered an injury in their 2-1 win at the Allianz Arena last Wednesday.
With Nacho still recovering from injury, the Morocco international and Theo Hernandez are favourites to fill the right-back role when Madrid host Jupp Heynckes' side on Tuesday.
But Valdano who guided the Santiago Bernabeu outfit to league glory in the 1994-95 season believes experience might count against the duo if played in such a crucial stage of the competition.“They [Hakimi and Hernandez] aren't going to be counted on for a match of this magnitude," Valdano told Marca.
"Both are skilled and have a bright future, but they need more experience before playing a European match of this stature.
"The atmosphere at the Estadio Santiago Bernabeu is corrosive, it's terrible for young players.
"Maybe it would be best for them to go to another team and then return."
Hakimi filled the right-back role in Saturday's 2-1 win over Leganes - his eighth appearance in the Spanish top-flight this season.
And Zidane is reluctant to rule out the chances of playing the 19-year-old who has made two appearances in the Champions League this season.
"Achraf is here. He is young. It's his first year with the first team," Zidane was quoted by BeSoccer after his team's win on Saturday.
"We have to be slow with him. We will see what we do on Tuesday. He played well [against Leganes]. He is learning. On Tuesday, you will see what we do."