Chelsea confirmed on Friday that Estêvão will miss the rest of the season with a hamstring injury.
It is not clear if the Brazil international will recover in time for the World Cup, which runs through June and July.
Chelsea interim coach Calum McFarlane did not give a timeframe for Estêvão's recovery from the injury sustained in the first half of last week's game against Manchester United.
"Estêvão unfortunately won't play for us this season because he is going to be out for a little bit of time. That's really unfortunate, especially for someone so young and so talented," McFarlane said. "I am sure he is very hopeful he can make the World Cup, but I don't know on that."
Estêvão, 19, was taken off after 16 minutes of the 1-0 loss at Stamford Bridge and missed Tuesday's 3-0 defeat at Brighton.
Former coach Liam Rosenior revealed last week that the teenager was in tears after being taken off. Hamstring injuries can take several weeks to recover from, or months in the most severe cases.
Brazil's first game at the World Cup is against Morocco at MetLife Stadium on June 13.
Estêvão joined Chelsea from Palmeiras last year and has scored eight goals this season. He was expected to be part of Carlo Ancelotti's squad for the World Cup in the United States, Canada and Mexico after scoring five times in his last six international appearances.
His injury is the latest blow to Brazil, which will be without Real Madrid winger Rodrygo because of a torn ACL and meniscus in his right knee.
Chelsea plays Leeds in the semifinals of the FA Cup on Sunday. Injured duo Cole Palmer and João Pedro could both be in contention to play.
