Former Chelsea forward Morata was first carded for arguing with referee Alejandro Hernandez, before moving his head towards Xisco Campos and saw red in the 77th minute. Just eight minutes after coming on as a substitute, he was walking down the tunnel.
Morata and Sevilla have engaged in a war of words since the final whistle, with the Atletico striker reacting angrily to questions on the topic, retorting: "Let him say it if he has b***s. I did nothing wrong."
Sevilla responded on Twitter: "At 35 years of age, I've always seen that what happens on the pitch has stayed there.
"My words were "you're a daddy's boy", as the video shows.
"It was a mistake on my part and I apologise. What I will not allow is for it to be said that I made comments about his wife and children."
Morata fired back in a tweet of his own: "As soon as I stepped on the pitch, only you and I know what you said to me.
"Indeed, the things that are said on the pitch remain there, so I won't say a word about what you told me. Good luck in the future."