Wales take on the Barbarians in a match dubbed the 'goodwill game' and the National Kidney Research Fund is appealing for people to help secure a world record by pledging to become organ donors at the event.
The Fund hopes to break the world record for the largest organ donor sign-up in one day and fans will be handed organ donor registration forms and cards as they enter the Stadium.
Janet Pardue-Wood, director of the National Kidney Research Fund in Wales, said: "This is a tremendous honour for us as Neil Jenkins has dedicated his final international appearance to the Fund and our Helena's Hope appeal to increase the number of organ donors. We wanted to mark the occasion with an ambitious attempt and hope that people will follow Neil's example and sign the donor card.
"If you've ever wanted to be in the Guinness Book of Records, now is your chance, and you don't need years of training to do it!"
The attempt is being carried out under Guinness World Record guidelines, will create a brand new world record and has the full backing of Jenkins, himself a world record holding points scorer in rugby union.
The legendary Wales fly-half already carries a donor card and is an enthusiastic campaigner for the Helena's Hope appeal, which is backed by the National Kidney Research Fund in Wales. The appeal was launched by Helena Jones, who has four children affected by kidney disease.
Two have already received transplants, but two more are among 400 patients in Wales who are waiting for suitable donors to be found to help to improve their quality of life.
"It will be a great honour for me to play one final time in the Welsh jersey and it will be extra special coming at the Millennium Stadium. But what will make it an even bigger occasion for me is that the game is being linked to the drive to find more kidney donors in Wales," said Jenkins.
"I've been a donor card carrier for quite some time. It's great to think that I might be able to benefit somebody when I die.
"It will be a very emotional moment for me on Saturday and I just hope Wales can give the fans something to shout about. It would be great to go out on a winning note, but we're going to need a lot of support and I hope to see as many fans at the game as possible."
You can get more information on organ donation and the work of the National Kidney Research Fund by calling 0845 300 1499 or by visiting www.nkrf.org.uk.