The Atletico coach played a key role in convincing Suarez to join Los Rojiblancos, and he has revealed that he discussed the Uruguayan's role with him over the phone.
"The moment I spoke with Luis on the phone I found what he gives on the pitch: a lot of desire and energy," Simeone said during Saturday's pre-match press conference.
"The team helps him to be at his best, which is scoring, something that has marked him throughout his career."
Joao Felix has experienced a drop in form in the last few games and Simeone believes that the Portuguese prodigy can give the team solutions when he is at his best.
"You always seek to focus on a footballer," Simeone added. "They have good, average and extraordinary moments.
"And as coaches we try to take advantage of every players' moments.
"We need Joao. When he is at his best, he can unbalance [the opposition's defence] and give different solutions.
"We need him in that version. It's what we are looking for in training."