Te Maire Martin played on with a collapsed lung on Saturday night in Brisbane's away loss to St George Illawarra before an overnight stay in hospital and a 12-hour car trip home.
The 26-year-old was unable to fly so was driven back to Brisbane from Sydney by Broncos football manager Steve Walters, who told AAP the 26-year-old seemed "OK and comfortable enough" on his return
Dr Matt Hislop, the Queensland team doctor who has worked with the Broncos, tweeted that Martin had sustained "blunt trauma to his back" in a tackle in Saturday night's 22-12 defeat to St George Illawarra, which ended the Broncos' season.
Hislop said Martin had "respiratory distress and went to emergency where a pneumothorax was confirmed". The pneumothorax, or collapsed lung, was "small and a chest drain was not needed", Hislop said.
Walters said the injury occurred in the first half but Martin continued to play until replaced in the 56th minute in what Walters terms a tremendous display of bravery.
"The injury happened in the first half and he just battled on," Walters said.
"He went back on in the second half but while he was out there it was really tender and he couldn't run properly.
"We took him off and that's when Selwyn Cobbo went back to fullback. It just shows how resilient Te Maire is. He is a tough little fella."
Martin was taken to hospital on Saturday night, where he stayed the evening. He was unable to fly so the Broncos secured a hire car.
"I drove him home and spent 12 hours in the car with him. He seems OK and comfortable enough," Walters said.
"We got back to Brisbane at 9pm last night (Sunday). He has to have some more scans but it certainly rattled him a bit. It was quite painful, I am sure."
Martin will join the New Zealand Warriors from next season after resurrecting his career at the Broncos following a bleed on the brain which kept him out of the game for for three years
"Te Maire is a terrific fella and his is such a good story with what has happened to him this year," Walters said.
"There are plenty of good news stories at the Broncos this year.
"(Forward) Zac Hosking is another one. He'd never played NRL before but he got his chance and now he has won a contract with Penrith.
"The other good news story is that we won 13 games this year, nearly double what we won last year. I can't believe how much people are bagging (the team)."
The Broncos lost five of their final six games to crash from fourth to ninth position after finishing 14th last year and securing the wooden spoon in 2020.