Just over a month after switching from Sydney FC to Norwegian champions Rosenborg, the gifted 18 year-old left-back - with just 34 senior appearances behind him - is competing with fellow rookie Brad Smith, of Liverpool, for a senior debut against Tajikistan in Adelaide or Jordan in Sydney.
Gersbach's’s ascension was a long shot ahead of experienced English-based pair of Jason Davidson or his recent understudy James Meredith – but ever adventurous coach Ange Postecoglou likes what he has seen from the attacked-minded defender.
And Gersbach is eager to make sure the boss's faith in his boundless promise is well founded.
“I guess it’s a bit if surprise, especially with Jason Davidson doing so well over the past few years and looking to have cemented a spot,” he said.
“But I knew I was in with a chance and was on the radar after receiving an email saying I as in the extended squad.
"I was really happy with that alone and it's surprising to see both myself and Brad picked. I didn’t think I’d make it into the final 23. When I got the message, it was a crazy feeling.
“I just can’t wait to get into camp now ... there's some healthy competition at left-back for sure now (with Meredith and Aziz Behich also in the mix).
“I am grateful for the chance … I aim to make the most if it and not look back. Of course, I would love to make my debut. If not, it will be no dramas and a great experience either way.”
The Olyroos defender is embracing a career which has been fast tracked as the future becomes the present.
“Everything so far in my career has happened so quickly. I have been given opportunities and I have been lucky enough to do well and take them," he added.
“This is another one – but it doesn’t mean anything yet until I play and do well and I will be working hard to make sure that happens.
“I have won my spot and I think I deserve to be there ... I am going to be confident and do my thing while respecting all those around me.”
While on the face of it 21-year-old Smith, who has four caps and has made an impression for Liverpool this season in cup competitions, might be favourite to start ahead of Gersbach, who can say for sure with the inscrutable Postecoglou at the helm.
“Hopefully myself and Brad can do a good job, whoever gets called upon in the first game (against Tajikistan)," Gersbach said.
“It’s a really strong squad, even though there are a lot of uncapped players.There's a lot of potential there.
“I have heard a lot of good things about Brad, and have seen some highlights and he looks like a great player.
“I can’t wait to get into camp and test myself against him and meet all the boys."
Yet to make acquaintances with big guns like Tim Cahill and Mile Jedinak, Gersbach will be undaunted.
“I have seen them at the World Cup but that’s about it ... it’s something else to look forward to (meeting them)."
Gersbach has featured in a clutch Rosenborg's pre-season friendlies and will be competing with established left back Jorgen Skjelvik for a start when the season kicks off this weekend with an away clash against Odd.
“Hopefully I will get a few minutes; we’ll just wait and see. I am just here to train, keep focused and prove myself. The aim is to get a lot of minutes during the season.
“I want to continue and be a part of an other successful season for the club. It’s just like with the Socceroos … I'll have to take my chances when they come.”