Marcus Rashford also scored twice on the day.
"There is no better stadium to score in," Zirkzee told MUTV. "I wanted to enjoy the moment, and Bruno (Fernandes) told me to take my moment as well, but I think I moved a little bit too quick back to the players (for the restart). It is a nice feeling scoring in front of these fans.
"I think what he (manager Ruben Amorim) asks for from the strikers is something very different to what me and Rasmus (Hojlund) are used to.
"We are just trying to adapt very quick and do what he expects of us."
On Amorim's early impact, he added: "Good. We are bonding really good, there are some strong connections. We all just want one thing and that is to be better every day and be back to top level in the league. There are some good spirits."
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