Llorente scored on Monday night, though lamented Atletico's defending afterwards.
He said: "There are positive things and things to improve, we conceded goals very quickly, we got the tie and they scored the second very quickly. These are things that cannot happen. But we knew how to level twice. The signings have to adapt.
"It is a sport of success and error, sometimes you fail and other times you succeed, it happens to all of us. These are things that can be improved.
"Happy to play again, to compete, which is what we like. In a beautiful stadium, with a very difficult opponent. A game that serves to gain rhythm, so that the new teammates adapt, who are going to be very important for us. To correct the things that we have had some things... to continue training.
"(But) when you concede two goals it is very difficult to turn the game around."