But even Mann-Rea knew he couldn't make a comeback after having a knee reconstruction as a 38-year-old.

The end of Mann-Rea's unlikely career has flown under the radar among the departures of several Brumbies stars, a Super Rugby finals campaign and the Israel Folau drama engulfing the sport.

He ruptured his anterior cruciate ligament during a game in Cape Town two months ago and knew almost immediately it was probably his last game.

The thing about the man better known as "Bongo" is that the challenges of a late-blooming career made everything more enjoyable, which is why he's still smiling despite a cruel injury twist.

"I guess everyone's career finishes at some point," Mann-Rea said. "To get another shot at professional sport like I did, I can't be that sad after seven years at the Brumbies.

"You just look at the next journey in your life and move on. Yeah, it is a bit sad. But it's life and I'll just miss being around 30 of your best mates every day."

Mann-Rea, the oldest player in Australian Super Rugby history and someone who never sought the spotlight, will join a group of nine Brumbies leaving the club at the end of their finals run, which continues against the Argentina Jaguares on Saturday morning.

He has been denied a fairytale finish on the field, but Mann-Rea says almost everything about his career was magical after getting a second chance later in life.

His salt of the earth attitude made him one of the most liked and respected players in Canberra and his happiness was infectious.

But it was the career that almost every was after the former Australian under-19s rake, who played in the same junior Wallabies side as Matt Giteau and Mark Gerrard, was ready to quit rugby to work in the Illawarra coalmines.

He made his debut for the NSW Waratahs in 2012 and the Brumbies signed him the following season, as a 32-year-old, to pave the way for Mann-Rea to live the dream he thought has passed him by.

BRUMBIES NEWS

He made his Wallabies debut and earned two Test caps in 2014 and played 69 games for the Brumbies despite having a knee reconstruction in 2013 and having his hamstring snap off the bone last year.

Mann-Rea was determined until the end. He refused to be taken off on a stretcher when he felt his knee pop and having ligament replacement surgery instead of a traditional knee reconstruction gave Mann-Rea an outside chance of playing as a 39-year-old.

"I felt the pop and I knew it wasn't good. It's just not my style to get carried off," Mann-Rea said.

"If my knee goes well, hopefully I can play a few games for Harden [in country NSW] next year.

"It's disappointing that I'm not playing finals because this is the good part of the year. But to be a part of it and to have the experiences I got ... I never thought I'd play for the Wallabies, that was a dream. I got to do a lot of things I never thought I would."

So what's next for Mann-Rea? He has been living in country NSW for the past three years after opting for a quiet life at Jugiong in 2016 and then shifting to Harden with his wife and daughters.

He spent three hours on the Hume Highway driving to and from Brumbies training every day and hopes to have a role in promoting rugby in regional areas. But he's keen to get his hands dirty on the land.

"I'd like to do something with the Brumbies next year as well," Mann-Rea said. "There's a few farming opportunities, so I'm excited about that. But the drive into Canberra every day was definitely worth it."

SUPER RUGBY SEMI-FINAL

Saturday: Argentina Jaguares v ACT Brumbies at Jose Amalfitani Stadium, Buenos Aires, 9.05am (AEST).

Brumbies: 1. Scott Sio, 2. Folau Faingaa, 3. Allan Alaalatoa, 4. Rory Arnold, 5. Sam Carter, 6. Rob Valetini, 7. Tom Cusack, 8. Lachlan McCaffrey, 9. Joe Powell, 10. Christian Leaiifano, 11. Toni Pulu, 12. Irae Simone, 13. Tevita Kuridrani, 14. Henry Speight. 15. Tom Banks. Reserves: 16. Connal McInerney, 17. James Slipper, 18. Les Leulualiaali-Makin, 19. Darcy Swain, 20. Murray Douglas, 21. Jahrome Brown, 22. Matt Lucas, 23. Tom Wright.

Jaguares: 1. Mayco Vivas, 2. Agustin Creevy, 3. Santiago Medrano, 4. Guido Petti, 5. Tomas Lavanini, 6. Pablo Matera, 7. Tomas Lezana, 8. Javier Ortega Desio, 9. Tomas Cubelli, 10. Joaquin Diaz Bonilla, 11. Matias Moroni, 12. Jeronimo de la Fuente (c), 13. Matias Orlando, 14. Sebastian Cancelliere, 15. Emiliano Boffelli. Reserves: 16. Julian Montoya, 17. Nahuel Tetaz Chaparro, 18. Enrique Pieretto, 19. Marcos Kremer, 20. Francisco Gorrissen, 21. Felipe Ezcurra, 22. Domingo Miotti, 23. Ramiro Moyano.