The Reds meet Auckland on Friday night at Adelaide's Coopers Stadium in the second leg of their semi-final after a 1-1 draw last weekend.
The victor advances to the decider against the winner of Newcastle's home semi against Sydney FC on Saturday night.
Adelaide linchpin Goodwin last played a full 90 minutes in mid-January before suffering a groin injury, logging just over 30 minutes from the bench in two games since returning.
"I'm ready to play whatever role is called upon me," Goodwin said on Thursday.
"I am fit enough and comfortable enough to play 90 minutes.
"But also, I know that if my role is coming off the bench, I have a part to play and can have a big impact."
Fellow veteran Ryan Kitto is available after overcoming a foot injury and joint Golden Boot winner Luka Jovanovic returns from suspension.
The 20-year-old Jovanovic's scoring has been a feature in the Reds' rise to championship contenders after most pundits had middling expectations.
"The outside can perceive us as underdogs all they want," Goodwin said.
"But when you have the focus and effort, the work ethic, and the quality on top of that, that's always going to give you a chance.
"We're in a position where we've done all of those things we talked about: the process, staying true to that; making sure that we improve the way that we're a bit more ruthless, a bit more relentless in the way that we play."
Goodwin described his own chances of earning a Socceroos call-up for another World Cup campaign as "an afterthought".
"I'm in a unique position here, that we have the chance to win the championship," he said.
"And that doesn't come around very often with Adelaide, obviously (we) never spend the budget as what the bigger teams do.
"So it's not something that is always there. And it's a privilege to be in this position and to try and win silverware for this club and for these fans.
"I know if I am going to have any chance of making the World Cup, then the next two games for me have to be unbelievable."
17°C