The 19-year-old Brazilian was forced off in the 16th minute in tears and will play no further part in Chelsea's season. Brazilian outlet Globo reports that he has chosen conservative treatment over surgery in an attempt to make the tournament, which opens on June 11.
Estevao has returned to his homeland and is currently undergoing rehabilitation at former club Palmeiras's facilities in São Paulo. Chelsea medical staff remain present throughout his recovery.
Opting against surgery keeps his World Cup hopes technically alive. Brazil's football confederation, however, have privately accepted that he is unlikely to be ready in time.
Chelsea's own doctors had recommended an operation. That would have guaranteed a longer but cleaner recovery — and ended any realistic prospect of tournament involvement.
Estevao had scored five goals in seven appearances since Carlo Ancelotti took charge of the Brazil national team, making him the head coach's top scorer in that period. He was considered central to Ancelotti's plans for the summer.
At club level, the winger posted eight goals and four assists in 36 appearances across all competitions in his debut season at Stamford Bridge after joining from Palmeiras for £29million last year.
His absence is a significant blow to a Brazil squad already without Real Madrid forward Rodrygo, who suffered a torn anterior cruciate ligament and meniscus earlier this season.
Brazil open their World Cup campaign against Morocco at the New York/New Jersey Stadium on June 13. Ancelotti will name his 26-man squad on May 18.
The winger's race against the calendar is one the medical evidence suggests he cannot win. Those inside the Brazilian set-up are not expecting him to be on the plane.