Madrid won 2-1 on Thursday evening to hold a slender advantage going into the second leg which takes place on February 28. Despite the victory, Simeone believes that the tie is still "very open".
Simeone told reporters: "The score sheet never lies, and I think that it was a fair result because that is how the game finished.
"The tie is still very open, 50/50, and either team could still win it."
Real Madrid or Barcelona await the winners in the final.