Coleman, one of the country's leading jockeys for many years, suffered a broken femur and serious pelvic injuries in a freak accident when the horse he was riding to the start for the 18th heat reared up and went over backwards when leaving the birdcage.
Coleman was rushed to Rotorua Hospital then airlifted to Waikato Hospital, where he underwent major surgery on his leg the following day. A pelvic operation followed a few days later and he was discharged from hospital on Monday last week.
"I had a few aches and pains leading up to this and this was just the shove I needed to say it was over," Coleman said.
"I've had a good career and have got nothing else to prove. I'm 51 now and by the time I complete the rehabilitation properly I'll be 52. I haven't talked to the surgeon about being able to ride again, but I know it would be too hard on the body."
Coleman served his apprenticeship under the guidance of astute Matamata trainer Jim Gibbs and he was the country's champion apprentice jockey in his second and third seasons.
In that second season (1986-87) he also rode his first G1 winner, kicking home stable representative Field Dancer in the 1987 Easter Handicap at Ellerslie. A week later the pair again combined successfully at Ellerslie in the G1 New Zealand Stakes.
Coleman went on to win 39 G1s, and boasted a remarkable record in that he has ridden at least one G1 winner for the last 20 years.
"I was lucky that I got to ride so many good horses and I got to ride for all the good trainers," he reflected.
"I'd rate the New Zealand Derby on Xcellent as one of my biggest highlights and I also got to win a jockeys' competition in Australia and run third in two Melbourne Cups. I also rode winners in Malaysia. I've got no regrets."
Coleman became just the seventh jockey to have ridden 2,000 winners in New Zealand when successful on August Edition at Matamata on June 1, 2017 and he took his record to 2,131 wins when successful on Vainglory on June 20 at Pukekohe, the first northern meeting since the return to racing after the COVID-19 lockdown.
"I'm going out on a winning note and that's something," Coleman said. "I was going quite well before lockdown. "I don't know what the future holds, but it won't be riding."