The Portuguese lavished praise on Friedel on Sunday night, and admitted it may take more than one bad performance to persuade him to ditch the former Liverpool man and hand France captain Hugo Lloris his first league start.
"We have made Hugo alert that whenever Brad has a bad game we won't (drop him). These things have to be taken very carefully," Villas-Boas said.
"We don't doubt Hugo's dimension and talent but at the moment we are paying respect to a player who is performing very well.
"At the right time we will think about it or not and Hugo is an extremely good professional.
"He wants to come back into the team but he is competing for the jersey and he will get his chance very soon."