Tom Parsons has undergone surgery following the horrific injury which he suffered during Mayo's loss to Galway in Connacht Championship quarter-final earlier this month.
On Radio One's Morning Ireland, Darren Frehill reported that the Mayo midfielder has dislocated his knee and suffered bad ligament damage.
"The operation in the early hours of Saturday morning took place at the Sports Surgery Clinic. It was just the first operation on the ligaments alone," said Frehill.
It was added that Parsons has been told that he suffered "one of the most unusual and rare injuries in sport".
In a statement released by Mayo GAA, it was said the operation was "the first part of two stages of surgery to repair his damaged knee structure."
The statement continues:
In the coming weeks and months, further specialist opinion, surgery and rehabilitation will follow.
Tom remains upbeat and positive and is extremely grateful for all the kind messages of support he has received from GAA colleagues, opponents and followers all over the world.
He will continue to receive the best possible care and support during his recovery process and all involved with Mayo GAA wish him all the best during this time.
Frehill also said that Parsons wished to thank all management and his Mayo teammates who have visited regularly as he recuperates from the injury.
Last week, Parsons tweeted to thank all GAA people for their messages of support. He added, "My comeback will be stronger than my setback".