Barry Johnston says his "heart broke" as he watched the full fallout from Marty Murray's horror injury back in 2019.
Johnston was managing St James' Swifts at the time and had convinced former Cliftonville teammate Murray to join the West Belfast club.
The then 26-year-old suffered a fracture to his tibia and fibula in an Intermediate Cup game against Windmill Stars, with the tie being abandoned as he received treatment on the pitch before being taken to Daisy Hill Hospital.
Read more: Cliftonville pay poignant tribute to ex-player on anniversary of death
Johnston - who is now manager of Lisburn Distillery - says the incident was a painful reminder of the impact a serious injury can have on a player.
He told Belfast Live's That's What I Call Football podcast: "When Marty Murray suffered his serious injury, it nearly broke me as a manager. It broke my heart.
"Because you bring him to the club, you feel it is your responsibility. After the game I was with him in the hospital and I watched the pain he went through.
"I had to watch him tell his wife and his brothers and mum, it was absolutely soul-destroying and you feel as if you can't go though that again.
"And you do feel a sense of responsibility."
Another former teammate Johnston managed to coax to St James' was ex-Cliftonville title winner Ryan Catney who suffered a double leg-break in 2017.
Catney - who left the Reds in 2019 - spent just one season with St James' before retiring from football.
Johnston says he had "no problems" with Catney walking away from the game.
"I had no problems when Ryan Catney saying 'that's me done'. He has a good job at Bombardier and a young family to think of," Johnston added.
"See when my knees went, I couldn't even get down and play with the kids.
"That's when you question why you're trying to get back into football. It is not worth it unless you're getting paid well and have your insurance.
"If you have family and priorities, and as painful as it is, sometimes you have to walk away for the good of yourself. Some players, especially young players who didn't make it, they target someone like Ryan Catney and try and be a gobs**** and try and do you.
"They don't realise the impact that tackle has on the player and their family.
"So I had no problem when Cats went."
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