And the players wanted to send a special match-day message to their partners, Katherine Bown and Sue Evans, who are both currently being treated for different forms of the disease, as well as encourage fans to join them in making online donations.
"After hearing about what both Katherine and Sue are going through the players wanted to find a way to help," said Wales fly-half James Hook.
"The pink armbands are just a small way of saying 'get well soon' to them both as well as, hopefully, encouraging fans to give money to cancer research.
"We are a close knit team and both Rhodri and Huw are very much part of that team and everything we do, so we also hope this simple gesture will show them both what they mean to us and help them through difficult times."
Fans who wish to donate can do so online and join the growing list of players' names recorded there, with both appeals currently in their infancy.
"We have been overwhelmed and humbled by the players' response and certainly did not expect a gesture of this magnitude," added Bown.
"The idea is that if everyone who becomes aware of the appeal just gives as little as £2 then the million pound target will be swiftly reached.
"Katherine is determined to raise the money for Cancer Research UK and what the team is doing for us should provide a real boost to reaching that million pound target."