The 26-year-old fringe Socceroo spent the past two seasons with Sparta Rotterdam in the Dutch Eredivisie, engineering the move after helping the Reds to the 2015/16 A-League double.
He marked his return to Adelaide with a goal in Wednesday’s 3-0 FFA Cup win over Central Coast.
Goodwin was named Adelaide’s Player of the Season during their successful 2015/16 campaign and returns as a key addition who could lift coach Marco Kurz’s side into title contention.
“I think I’ve grown a fair bit,” Goodwin said. “It’s the top division so it’s a good competition playing against some good players and some really good teams.
“I really enjoyed my time over there. I learned a lot about the game, different styles of play, the intensity of the game and the speed.
“I’ve definitely learned a lot from my time abroad. I’ll be looking to implement that at Adelaide.”
The left winger helped Sparta avoid relegation in his first season in the Netherlands, netting a goal and provided two assists in their decisive final day win.
He departed late into his second season after falling out of favour under coach Dick Advocaat but said the experience abroad had made him a better player, particularly mentally.
“You’re always learning,” he said. “You can always improve your ability no matter what age you are.
“You’ll have a foundation of where you are and I think you can always improve by practising. I certainly feel like I’ve improved a lot from my time abroad.
“Maybe not from the skills side, but a lot from the mental side and the speed of thought. The different tactics have made me a much smarter player than when I left.”
Adelaide-born Goodwin was thrilled to score on his return to his hometown club.
“It was very nice to get on the score sheet in front of the home fans again,” he said. “Hopefully a lot more of them to come.
"We’re very happy with the team performance and getting through to the next round of the cup. It’s a competition we want to do very well in this year.”