The 34-year-old confirmed earlier this week that he will depart the club, where he made his name as a young striker, when his contract expires at the end of the season.
Torres, who returned to Atletico in 2015 on an initial loan deal, has been waiting for his landmark La Liga goal since hitting the net against Las Palmas in January.
He finally brought up three figures with a superb volley to complete the scoring in the comfortable win, leaving Simeone to heap praise on the former Spain striker.
"Fernando is an icon here, whether he's scoring goals or not," he said in his post-match press conference.
"He's earned this status and respect through hard work.
"When I called him to sign for us, I told him I wanted him to come as a football player and not an idol.
"Fernando's performance was as important as that of the whole team.
"We made three very beautiful goals, and having everybody pulling in the same direction is what works for the team.
"People care that Fernando has incredible feelings for this club, it makes me happy to have helped him live with this team once again."
The victory moved Atletico back to 11 points behind La Liga leaders Barcelona.