Players, staff and supporters at Valley Parade are still coming to terms with the devastating news that 29-year-old Darby is suffering from motor neurone disease.
“It has hit everyone hard,” said Doyle about the Liverpool-born full-back, who twice played at Wembley for Bradford during his five years in Yorkshire.
“Same at every club he has played for. You can see that on social media, everyone saying their piece.
“That is testament to him and the type of player he was. I can’t stop thinking about it and I am not even close.
“It is an awful, tragic thing that he and his family are going through. David Ball played with him, while Nat (Knight-Percival) was here at the same time.
“Then, there is obviously the medical staff, who were all very close to him. You can see it has affected people.
“I live in Liverpool so I have a lot of friends who are very close to him. I only ever heard good things about his character and the type of lad he is.
“He should be coming into his prime years now. It is a horrible, horrible disease. One of the worst things out there.
“I hear he is mentally a very strong lad. That will help him massively. ”
Darby made 239 appearances for City before following Phil Parkinson to Bolton Wanderers last year. He retired earlier this week after being diagnosed with the fatal illness that claimed the life of former Leeds United manager Don Revie in 1989.
Doyle, who joined City this summer, added: “It is devastating. I can’t imagine what ‘Darbs’ and the people closest to him are going through. Us, as players, are here for him. Whatever he needs. We will jump to it.
“We definitely go into the game with him on our minds. It would be nice to get the three points. We are due a performance anyway but this is an extra little kick for us.”
Head coach David Hopkin revealed City had been in touch with Darby’s agent to ask if there was anything the club could do to help.
The Scot added: “I didn’t know Stephen but everyone I spoke to at the club said he is a fantastic person and player. At this moment, he just wants privacy. We have got to respect that as a club and give him his space.”