A Spain international and one of Atletico’s most creative influences, Koke missed last month’s first leg defeat in Germany due to injury but has featured in Atletico’s last three outings in La Liga.
The 23-year-old, who scored in this month’s 1-1 draw at home to Valencia, is also a dead ball specialist and the Spanish champions have netted a host of goals from his corners and free kicks.
“He is one of those all-round midfielders who is gifted at reading the game, he knows how to play in different positions in the centre and he has very good peripheral vision,” Simeone told a news conference.
“When he is on top form, he allows us to play with speed. Not because he is fast himself but because his vision allows us to play that way.”
Atletico, last season’s beaten finalists, have been struggling for goals in recent weeks and have only scored once in their last four outings in all competitions.
Elimination on Tuesday would almost certainly rob them of their last chance of silverware this term as they are out of the King’s Cup and slipped nine points behind La Liga leaders Barcelona after Saturday’s 0-0 stalemate at Espanyol.
Forwards Mario Mandzukic, Antoine Griezmann and Fernando Torres have been off colour and Atletico have failed to score in three consecutive away games in La Liga for the first time since Simeone took over at the end of 2011.
Leverkusen, by contrast, have racked up 11 goals without reply in winning their last five games in all competitions, including Friday’s 4-0 drubbing of VfB Stuttgart.
Simeone said breaking out of defence swiftly would be one of the keys to Tuesday’s clash at the Calderon.
“We need to shake off their pressuring quickly when they are trying to win back the ball,” Simeone said.
“They know very well how to disrupt play and hold you up,” added the former Argentina captain.
“That’s what happened in Germany. They stopped our attacks quickly with fouls and we couldn’t develop our vertical game. If we don’t take the ball forward quickly we will have problems.”
(Editing by Pritha Sarkar)