The 27-year-old sustained internal injuries when he was legally bumped by West Coast's Andrew Embley during the Magpies' semi-final win over the Eagles at Patersons Stadium on Saturday night.
He was admitted to hospital after the game and developed bleeding from his kidneys, which was expected to keep him in hospital for at least a week.
However, his condition stabilised on Monday and he was told he could travel home to be further monitored by the club's doctors.
"He didn't get the all clear to come back until late in the afternoon Perth time and he caught the flight back last night and he's been given the okay to stay at home and rest, rather than stay in hospital," Collingwood media manager Nick Hulett said on Tuesday morning.
"He'll stay at home and rest for as long as he needs to and then over the next week or so he'll be monitored on a day-to-day basis, and we're hoping he'll be back on his feet pretty soon."
Maxwell applauded Embley's bump on Twitter on Monday, calling it a "ripper" with "perfect execution", which was echoed by teammate Darren Jolly on Tuesday.
"It was a good bump, a fair bump and I think [Maxwell] just had a bad case of being winded in the end," he said before training.
"He's milked it for all he can get.
"His ribs are fairly sore. I think we just have to wait and see how bad they are."
Maxwell will miss this Friday night's NAB Cup grand final against Essendon and is in doubt in round one of the season proper.
Jolly said senior coach Mick Malthouse would step back into the driver's seat this week after letting his assistants rotate through the main job across the NAB Cup.
He said the Pies were looking forward to the pre-season competition going up a notch when they play off for the NAB Cup title against the Bombers in front of what is expected to be a huge Etihad Stadium crowd.
"With any grand final, the stakes probably will go up a little bit," he said.
"A bigger crowd, the hype around Essendon, and it's a good experience for us to lead into round one."
He also said the Bombers would be formidable opponents after improving their contested ball use and implementing some of the Pies' tactics surrounding the defensive press.
"They've got a good list and they've had a lot of hype over the pre-season, with James [Hird] and new coaches coming along," Jolly said.
"They're quick, they're lively and they've got great enthusiasm so the way they're playing at the moment is really, really dangerous for us and we'll watch them closely and really have to be on our game to be in with a show."
Heath Shaw, Chris Tarrant, Luke Ball and Leigh Brown are among those expected to be recalled to the side after being rested from the trip to Perth while Alan Didak remains a strong chance to play his first game since last year's grand final replay.
Nick Maxwell is a $257,000 defender in this year's Toyota Dream Team competition.
