From the HSC to the big one for Sydney teenager Gersbach

Sydney FC defender Alex Gersbach only sat his final school exams a few months ago but now he's preparing for the biggest test of of all - his first A-League grand final.

Alex Gersbach hopes to get back into the starting XI for Sydney FC after losing his place in the back end of last season Source: AAP

The 18-year-old left-back admits he's nervous ahead the epic title decider against Melbourne Victory at AAMI Park on Sunday.

He was a regular in coach Graham Arnold's side in the first half of the campaign, making 16 starts but looks set to be a substitute on Sunday.

Nikola Petkovic appears set to start in the left-back position with Arnold likely to field the same starting XI that demolished Adelaide 4-1 in last week's semi-final.

Sitting his HSC exams just last November, Gersbach had to juggle the first few rounds of his maiden season in profession football with intense study.

He says he still can't believe the whirlwind season he's had.

"Yeah I'm nervous, I think everyone feels nervous before a grand final," Gersbach said. "But it's more excitement I think.

"It's been amazing. I came into the team and had to do my HSC at the start of the season and got through that pretty well.

"Now we've made the grand final that's just topped things off. It's unbelievable.

"So to win it would just be amazing."

With the final being played at the relatively small 30,000-seat AAMI Park, only 3500 tickets will be reserved for Sydney FC fans.

Melbourne-born Sky Blues midfielder Robert Stambolziev, who is also set to be on the bench for his first A-League grand final, will have the support of his family in the crowd.

Should he get game time on Sunday, it will be the first time in his professional career he'll get to play in his home town in front of his family.

"Going back home and playing for the first time in Melbourne with Sydney FC for me personally it would be really special," he said.

"But's it's a special day for everyone in the team."