Ratcliffe overcome an "absolutely abysmal" warm-up to put on a supremely consistent display of throwing at Carrara Stadium, pouncing when her main rivals failed, to claim gold with a best throw of 69.94 metres.
The 24-year-old had claimed silver in Glasgow, with a best throw of 69.96, but she produced a top display in wet conditions to win New Zealand's first ever gold medal in the discipline.
"I wasn't expecting it," admitted Ratcliffe. "This competition, I've wanted to win it more than any other. It was probably one of the best series of my life out there. Even though it wasn't the biggest distances, it was the most consistent."
Why was her consistency important? Well, as she reeled off six consecutive throws between 66 and 70 metres, her main rivals – Canada's Jillian Weir and Olympic bronze medalist Sophie Hitchon of England - both failed to record a legitimate throw on their first three attempts. As a result, they were stunningly eliminated from the competition when the field was culled to eight halfway through the event.
All of a sudden, Ratcliffe was the woman to beat, a fact she soon realised while watching on.
"I saw Sophie's foul, and Jillian had already left, and I was sitting there thinking "I could win a gold medal right now" - it was just so incredible."
It was also a significant contrast to her warm-up; a horror beginning to a day which looked like it could end up in disaster for the Hamiltonian.
"I had an absolutely abysmal warmup, honestly, I thought I was going to lose it, completely, but I managed to pull it back together.
"It honestly looked like someone had been picked out of the crowd and said "Have a toss" - I don't know what happened. I'm proud I managed to get it back cause I was a bit scared for a second."
It ultimately had no impact on her performance when it mattered, with Ratcliffe setting a strong early standard. Her second throw of 68.60 was nearly matched by her fourth attempt of 68.56 – both throws better than anything her competitors could muster.
Her early efforts gave her a 60 centimetre lead over Australia's Alexandra Hulley, and Hulley proved to be her only remaining rival as the event ticked down to a thrilling conclusion.
There, Ratcliffe found a new level, with her penultimate throw of 69.94 metres giving her breathing room.
She ultimately didn't need it, with Hulley failing to fire on her last two attempts, and Ratcliffe taking home a stunning gold.
