Ellis says the idea to form a boy band was something he and his Crusaders teammates had been thinking about for some years.
"Ensuring there are options for us after rugby was a big motivator."
Dagg says the selection process to get into C-City Brothers was "fierce".
"Andy held auditions and all members of the Crusaders gave it a go. At the end though, he was in awe of our skills."
Op Shop star Jason Kerrison collaborated with Ellis to write Never Walk Away.
All the proceeds from single sales are going to Cystic Fibrosis NZ.
Its chief executive Kate Russell says she is touched by the C-City Brothers' generosity.
"Everyone at Cystic Fibrosis NZ has known for a long time just how talented these guys are on and off the field, but to have them using their talent to help us in our work for people with CF is just so heart-warming. We are sure this is going to be a stellar hit and these guys are going to go far."
Never Walk Away is available on iTunes today.
The C-City Brothers are expecting to be performing live over the summer.
- nzherald.co.nz