The France international scored twice in a lethal first-half display and went on to go close with several other opportunities after the break, while also claiming an assist for their third – a Manucho own-goal.
A hat-trick narrowly eluded Griezmann, with the post denying him a marvellous solo effort in stoppage time
Simeone was delighted by the former Real Sociedad star's display, particularly with regards to his work rate.
"We have been saying it since November - he has grown a lot and is the type of player we need," the Argentinian was quoted as saying by AS.
"But besides his goals, I value his work capacity that he gives the team. He is demonstrating that you can not only play out wide, but anywhere in the attack and he can break with his speed and talent."
Simeone introduced Fernando Torres in the second half and the former Chelsea man enjoyed a lively cameo, with his coach expecting him to flourish once settled into his second spell with Atletico.
"I saw him with the same enthusiasm as always," Simeone added. "He scored two goals in the Bernabeu [in the aggregate Copa del Rey win over rivals Real Madrid], he did very well in the first half against Barcelona and had a couple of chances.
"Little by little he will gel with his team-mates. With spaces in attack, he is a player that is very difficult to mark."
