The Magpies were beaten 3-2 by Alex Neill’s side on Saturday afternoon as a last-gasp goal from Marcus Olsson sealed all three points for the home side.
It was a major blow for Newcastle’s hopes of avoiding relegation from the Premier League, with the win taking the Canaries four points clear of the bottom three in 17th place.
The manner of the defeat was hugely demoralising for Rafael Benitez’s team, and Mitrovic has said that the best way to get over that is to beat Southampton in their next game.
“We lost, and we need to move on and prepare for the next game,” he told nufc.co.uk. “It's much better if you score goals and you win. I don't need to score if we win games. But it's good for me, of course, and I hope I will continue with my goals.
"The best way to move on is to win the next game. It will be difficult, Southampton away, but we must stay strong in our heads. It's difficult now but we need to start winning games."
If Newcastle are to start winning games to secure their survival this season, then Mitrovic is looking key to those hopes.
The striker has struggled in his first season in England, although St. James' Park has hardly been the right place for him to thrive.
Recent weeks have seen him step up though, with a goal against Sunderland and two against Norwich City surely making him one of the first names on the teamsheet for Benitez.