Atletico cruised to a 3-0 win via goals from Antoine Griezmann, Marcos Llorente and Koke.
Simeone said, "We were facing an opponent who had an extraordinary last season, with different ways of attacking that invite you to split, that creates difficulties and I place great value on concentration and never losing the block that prevented them from having scoring chances and an offensive game.
"The goal created more security for what was to come in the second half, which we were able to handle with great confidence and a strong, fast counterattack, with the players who came on from the bench giving us what we needed from the game."
On Alvarez, he continued: "Normally, important footballers demand that things happen. People go to the field to see them and they cause situations to happen, we know what Julián has, what he can give us and we will seek to exploit his best conditions whether as a striker, second striker, on the side and we are convinced that we have a player of incredible present and future and as (Antoine) Griezmann says we lack the connection that time will give us.
"Julián gave us a lot of work for the team, he almost always occupied places so that we could generate ball recovery, counterattack perspective, he participated in the second goal to generate space and he will want more and will be looking to reach the goal like (Alexander) Sorloth, (Angel) Correa want. The footballers from that area have friendship with the goal."