Following the 2-0 win, Simeone was asked about goalscorer Griezmann's future.
"I'll repeat, he's one of our captains," Simeone said at his post-match press conference.
"The club has made an enormous effort to keep counting on him.
"He's happy in Madrid, he's important to this team and nothing makes me think he's leaving."
Oblak is another player likely to attract attention from any club seeking a goalkeeper, and Simeone believes his No.1 is the best around.
"He's the best in the world," the Argentine said.
"We're lucky that he chooses to play for us.
"He makes us proud, I hope he keeps growing because he's improved since the day he arrived."