Calvert-Lewin is a former Sheffield United player and also was a Blades fan growing up.
He said at the final whistle: "I'm happy to be back with a goal. I have worked hard to get back in top shape. I know that when the ball is in the box, I have to be ready, so I was happy to put it in.
"When you get in front with 1-0, then you are never sure, so we had to score one more to be sure.
"It felt good to have one against them - especially because I was a Sheffield United fan as a boy."