Goodwin, who was mostly being used in his preferred spot as a winger by coach Guillermo Amor, has played five straight games at left-back heading into the big game against Western Sydney Wanderers at Adelaide Oval on Sunday.
Regular left-back Tarek Elrich missed the last five rounds of the regular season with a groin injury. Jordan Elsey played the first game at left-back in his absence and then Goodwin was moved there.
Elrich returned to the squad for last Friday's semi-final against Melbourne City, but started from the bench with Goodwin again at left-back. Elrich didn't get on until the 80th minute, replacing Goodwin.
It seems likely that, due to Elrich's recent lack of game-time, Amor will start with Goodwin at left-back again, but Goodwin told said the coach had not revealed his plans to the players at this stage.
"I don't know myself yet," Goodwin said. "Obviously the coach has got to make a decision and he may want to keep it the way it is or he may want to bring Tarek in, so I've got no idea what's going to happen.
"Last week I trained at left-back, but so far this week we've had relatively light sessions on Monday and Tuesday, with Wednesday off. Training increased on Thursday and we're doing all those kind of tactics from now on.
"But I'll be comfortable whichever position I play. I've played left-back for the last five games and I'm comfortable there and if I play wing I'm comfortable there as well."
Goodwin can handle left or right wing, but Sergio Cirio and Bruce Kamau have been doing well at left and right respectively for Adelaide recently, which probably increases the chances of Goodwin staying at fullback.
It appears unlikely Goodwin would be shunted all the way back to the bench, as he has been an integral part of Adelaide's success this season.
"It's great to have virtually the full squad available again," Goodwin said. "Everyone is on deck except Eli Babalj, who was obviously injured very early in the season.
"There have been quite a few times this season when I've been on the right wing and Cirio on the left and we've chopped and changed during games to keep the defenders guessing.
"And Kamau has been doing well since he has come in, so it's tough competition for places and I guess the coach has got to make a decision about what he thinks is best for the team.
"It's one of those ones where even when you're involved in the team you're not sure yourself what's going to happen.
"I guess you just have to do your best in training and wait and see what the coach does, but we've got a good squad and whether you're starting or coming off the bench everyone knows they've got a part to play."
Goodwin, 24, is in the final year of his contract with Adelaide and hopes to try his luck in Europe. It was recently reported there was interest in him from clubs in the Dutch, Belgian and Austrian leagues.
Asked if the grand final would be his last game for Adelaide, Goodwin replied: "I'm not sure, we'll have to wait and see. There is nothing been set yet, but I've got one more game this season and we'll see what happens after that.
"I think the club and I are just waiting until after the season and then we'll discuss what's going to happen with me. I'm purely focused on the grand final and wanting to lift the trophy at the end of it.
"It has always been my dream to try my luck in Europe and try to play in one of the top five leagues over there. If an offer comes along I'll definitely have to look at that, but I'm at Adelaide at the moment and if it ended up that I stayed here for next season I'd be more than happy as well."