The injury kept him from playing for Team Europe at the World Cup of Hockey 2016 and prevented him from skating with the Maple Leafs when they opened camp Sept. 24 in Halifax, Nova Scotia.
But Andersen, 26, showed no signs of rust Wednesday and took part in the entire practice.
"Still day to day, but it's been going pretty good," Andersen said. "I feel pretty strong and working hard in the gym, too, to be back. Today was another step forward."
Toronto acquired Andersen in a trade with the Anaheim Ducks on June 20 and signed him to a five-year contract reportedly worth $5 million per season. He's already made a good impression on some of his new teammates.
"Everybody that I've talked to about him have nothing but good things to say [about] how hard he works, how good he wants to be, how good he can be, and just what kind of person he is," defenseman Morgan Rielly said. "That speaks volumes about a person, when his old teammates have all kinds of things to say about him."
Andersen took part in the second of two practice sessions Wednesday, working out with rookie Antoine Bibeau and newcomer Jhonas Enroth. The Maple Leafs will be patient and not rush Andersen into preseason games.
"I don't know. He's feeling better, that's what we like," assistant coach Jim Hiller said. "We saw him in the practice. I thought he did great, but beyond that I can't comment."
Andersen played an NHL career-high 54 games with the Ducks in 2014-15. After seeing the level of young talent with the Maple Leafs, Toronto was an attractive destination.
"I'm really excited about this year and playing for this franchise is going to be huge," he said. [It's] a really cool experience and I look forward to getting this team back into the playoffs. That's the first goal, and everyone has been working hard in the summer to get towards that goal."
