The Brazil international missed Chelsea's 2-0 win over Liverpool at Anfield last weekend, and remained benched in their 3-1 defeat to Atletico Madrid in the UEFA Champions League semi-finals on Wednesday.
A hip injury is keeping Oscar out of the side, rather than his performances, and he remains eager to play a part for Jose Mourinho's side in the run-in.
However, the 22-year-old remains cautious over his comeback - citing a worry over the injury and potentially missing out on the competition in Brazil later this year.
"I'm not playing because I felt a pain due to an injury to my hip so in the last game against Liverpool, I was not called on," he told Globo Esporte.
"I warmed up (on Wednesday) but Mourinho knew that I could hardly play.
"Maybe I will not play the next game (against Norwich City) because I could suffer a more serious injury to my hip and he knows it.
"We're aiming to try and play me in the final clash of the Premier League (at Cardiff City) but I have to take care for the World Cup.
"We still have two very important games in the Premier League because Chelsea can still be champions.
"But it is important I rest because the World Cup is here (in Brazil)."
