Chelsea went in at the break a goal down in Wednesday night’s match at the Wanda Metropolitano after Antoine Griezmann scored from the penalty spot five minutes before half time.
However, Morata struck the equaliser for Chelsea just before the hour mark and, in injury time, Michy Batshuayi turned home a cross to snatch all three points for the visitors.
“It is a very important win for us. It was a big test,” the Spaniard told BT Sport. “Atletico Madrid were in the Champions League final a few years ago and now we can go home relaxed and put this mentality into the Premier League.
“It is always a good feeling to score the first goal in a new stadium. I am very happy. I am happy with my start but the most important thing is the team and winning the game.
“It is great to play with a player like Eden Hazard. He is one of the best in the world and I am very lucky to play with him.”