The former Porto ace put in a man-of-the-match performance to help the Primera Division side to victory against Chelsea in the Uefa Super Cup on Friday evening in Monaco
The Colombia international netted a first-half hat-trick to help Los Rojiblancos to a comfortable victory against the Champions League holders, and Simeone was lost for words after the prolific hitman's impressive display.
"I'm speechless. I really can't describe it. What Radamel is doing is indescribable," Simeone stated at a press conference.
"He's a lad who whenever you set the bar high he sets it higher and rises to the occasion. He has dedication above and beyond what is normal.
"I've known him since he was very young and he's always demanding; pressure is his source of strength. He's an excellent player.
"He works to improve every day and his motivation is infectious for the whole squad. Hopefully we can enjoy him at Atletico for a long time."
Falcao joined Atleti from Porto in the summer of 2011 and has since become a key player at the Liga side.