The former Anderlecht star played his first game for the Magpies since a £13 million move.
Newcastle United slipped to a disappointing friendly defeat to League Two side York City on Wednesday night, but there was at least one new arrival on display for Magpies fans to get excited about.
The Serbian striker was prolific in his time at Anderlecht, scoring 44 goals in 90 matches in his two seasons in Brussels, despite only turning 20 last season.
At Bootham Crescent, Mitrovic started the match and played for 70 minutes, before being replaced by youngster Lewis Suddick, and the striker had a number of narrow misses as he sought to grab a goal in his first game.
Anthony Straker lobbed Karl Darlow to open the scoring in the first half, before trialist Reece Thompson netted a great effort to double the lead, with Ayoze Perez scoring a late consolation for the visitors.
Having missed several pre-season matches at Anderlecht while his move to St James's Park was negotiated, Mitrovic will likely be a little behind his teammates in terms of working on his match fitness, but give him a little time, and the Magpies could well have a real player to unleash on the Premier League.