The Argentine was content with what he saw as his team booked their place in the next round of the Copa del Rey, though, he admitted they could have been sharper in attack
Los Colchoneros headed into the tie with a 3-0 advantage following the first leg, and in the words of Simeone, "did what they had to" in the second on Thursday night to ensure their place in the quarter-finals.
"We defended well and protected our advantage, we did what we had to do," Simeone told Marca.
"In terms of attitude and the performance, there is nothing to say. Perhaps we lacked a bit in precision in the final play and we had situations that we could have done better in finishing off."
Since his arrival in the Spanish capital, Simeone is yet to lose a knockout match either in Europe or the Copa del Rey, however, he is keeping his feet on the ground.
He added: "It is going well for us now and we hope to continue working hard come the next knockout game.
"I think it will be difficult whether it is Las Palmas or Betis, they are both tough rivals and with them we will have to have full focus."
The trainer lamented the absence of Adrian who was ruled out just before kick off, while he downplayed star striker Radamel Falcao's part in the sending off of Lopez Gomez Rafa in the first half.
"This is football. These things happen in games. The referee can only interpret the best he can," he continued.
"We hoped that Adrian would play. He would have given us more speed on the right and with Cristian on the left and Falcao up front.
"We could have played a little more vertically. However, he could not play and we hope that tomorrow [Friday] he will be better."