The former Sydney FC defender played 90 minutes as Rosenborg went down 2-1 at home to Tromso.
Gersbach has now started in five of Rosenborg’s nine league matches this campaign, with one appearance off the bench.
Despite the loss, Rosenborg remain at the top of the Norwegian Eliteserien after nine matches.
They next face strugglers Lillestrom at home on Sunday.
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