The 23-year-old, the lone Caribbean runner in the final, clocked 20.11 seconds as he followed home winner Ramil Guliyev of Turkey who was timed at 20.09, and silver medallist Wayde van Niekerk (20.11)
The race for the medals went down to the finish as Richards, who was off the curve in fifth, fought back gallantly but was just out-dipped on the line by van Niekerk as both recorded the same time.
Richards said afterwards he had botched his start so to recover and secure a podium finish was a “great achievement.”
“I slipped coming out of my blocks and into my drive phase,” he explained.
“I tried my best not to let it affect me too much. At the turn I wasn’t in contention really, so to get a medal from there is a great achievement.”
He continued: “This means a lot to me. I always wanted to bring a medal back home for my mother. I do everything for her, so I am so happy I can take her the bronze.
“Words alone can’t explain how grateful I am to be in this position and be lucky enough to perform here.”
Meanwhile, Jamaica’s Ristananna Tracey handed the Caribbean its other medal when she also clinched bronze in the women’s 400 metres hurdles.
She produced a personal best 53.74 to finish behind Americans Kori Carter (53.07) and Dalilah Muhammad (53.50).
Tracey trailed the duo off the final curve, battled with Zuzana Hejnova of Czech Republic before proving stronger over the last 50 metres.
“It was a very strong race and I kept telling myself not to panic. Off the last hurdle I gave everything and threw myself for a dip just in case. It was so great and it can only get bigger from now,” explained Tracey.
“I want to be the world’s best before I retire. I was fifth in Rio and I have stepped up here. There is hopefully more to come from me in the future.”
Two Bahamians – Shaunae Miller-Uibo and Tynia Gaither – will contest Friday’s final of the women’s 200m.
Miller-Uibo, who finished a disappointing fourth in the 400m final on Wednesday night, recorded the joint-leading time of 22.49 while Gaither was timed at 22.85.
Jamaicans Sashalee Forbes (23.09), Simone Facey (23.01) and Jodean Williams (23.32) all missed out on the final along with Bahamian Anthonique Strachan (23.21) and Trinidadian Simoy Hackett (23.54).
Trinidadian Keshorn Walcott, meanwhile, the London 2012 Olympic gold medallist, advanced to the men’s javelin final after throwing 86.01 metres.
- Countries: Caribbean