Vidal misses out after sustaining a calf strain during Juve's 3-0 win over Napoli on Sunday, while Palmeiras playmaker Jorge Valdivia will undergo a late fitness test to determine whether or not he will be able to play.
Sampaoli said that Vidal would also miss Tuesday's friendly game against Brazil in Toronto, meaning he will not be able to turn out for his country until they play Germany in March next year.
"It's a complication. Basically for all the time, we have to wait until that match," said Sampaoli. "Arturo's absence is very significant."
Chile booked a place at next year's FIFA World Cup™ with a run of five wins and one draw in their final six qualifying games and Sampaoli expects his side to carry that momentum into the games with England and Brazil.
"It's very, very important as part of our preparation," he told a press conference at Wembley Stadium on Thursday. "These next two friendly games, against top world sides like Brazil and England, will give us an idea of where we are and how we're going to compete in the World Cup.
"We know those two sides are going to give us a real stiff test and that's important for us. Any mistakes you make, they don't let you off. For me, the World Cup starts on Friday.
"Irrespective of what the line-up is, it's important we hit our straps and treat it like it's the World Cup. It's a competitive match for us."