Gersbach started and played a full game at left-back for the Norwegian league and cup winners who triumphed thanks to goals from Milan Jevtovic and Tore Reginiussen.

The 19-year-old was left out of Ange Postecoglou’s latest Socceroos squad due to a lack of game-time during the Norwegian off-season.

The ex-Sydney FC man had only just returned to Norway after spending last week with the Australian Under-23 squad for a training camp in Spain under Josep Gombau.

Australia drew 1-1 with Austria’s Under-21s and lost 2-0 to Finland’s Under-21s.

The Tippeligaen resumes this weekend with Rosenborg at home to Odd on Sunday.

Gersbach has played in all eight of Rosenborg’s pre-season matches, starting six of them, plus Wednesday's Super Cup clash.