Atletico welcome Barcelona to the Vicente Calderon for the second leg of their quarter-final on Wednesday, with the two sides level at 1-1 from the first leg last week.
Costa was forced to exit in that match after picking up a knock and it is widely expected that the Spanish international will not be available for the European tie.
"We will see what condition he is in at training," Simeone told reporters at a press conference.
"If he doesn't play Adrian [Lopez] will and I am sure he will do very well.
"The team needs a player who is at a minimum of 90%. A player at 50% does no good, whether that be Miranda, Diego Godin or Diego Costa. Adrian is in good shape and I am sure that tomorrow he will score a goal!"
Arda Turan is also an injury doubt for Atletico.