It was the second game in a row that the defender had missed, having not played in the [1-1](/sport/football/man-utd-west-ham-boos-old-trafford-b1261230.html) draw with West Ham last week.
That turned out not to be the case, and de Ligt was nowhere to be seen in the matchday squad.
In his post-match press conference, Amorim remained tight-lipped about a potential return for the centre-back.
"I don't know, sometimes you have an idea then you have to see day by day,” the head coach said.
“I'm not going to say when he is coming back.”
In de Light’s absence, youngster Ayden Heaven started once more in the middle of the back three, with natural right-back Noussair Mazraoui on the right of the trio.
Luke Shaw was on the left as normal, but Mazraoui and Heaven were replaced in the second half by Leny Yoro and Lisandro Martinez, who is continuing his comeback from an ACL injury that he suffered back in February.
The Argentine made his full return off the bench in the [2-1](/sport/football/crystal-palace-vs-man-utd-premier-league-result-b1260449.html) win at Crystal Palace the week before last.