The classy 5yr-old produced a big finish in the weight-for-age 1400m race, her fifth group 1 success. She was ridden by Michael McNab.
Melody Belle came into her Tarzino Trophy defence after finishing fourth in her first race of the season in the Foxbridge Plate at Te Rapa last month.
Though she ran creditably, the Te Akau stable's trainer was hard on himself for not having the mare slightly fitter for her first-up run.
"I just kicked myself first-up as we needed to do a little more in her trial at Te Rapa," Richards said.
"She was beaten fair and square [in the Foxbridge] but I knew the 1400m was really going to suit her and she has done a terrific job."
Her Foxbridge Plate effort proved to be the hitout Melody Belle needed to get her to her peak for Saturday's group 1 assignment.
"She came through that last race well, ate well and did everything right," Richards said.
"She's just a champion."
Melody Belle's slow start from barrier 15 gave McNab no option but to ride patiently. The 5yr-old drifted well off the hectic speed set up by rank outsider Deerfield.
"We stepped slow and I thought that was Plan A definitely gone as I was going to go forward," McNab said.
When he saw an opportunity to track the favourite, Endless Drama, he jumped at it.
"I went back and got in, and across the top I saw Endless Drama out posted and I thought he would take me far enough [into the race].
"We chased him and then sucked up and sucked up and when she got out, she let rip - just an amazing horse.
"She's a no-frills type of horse and just a real warhorse."
Once McNab angled Melody Belle into the clear in the straight she unleashed a powerful finish to win.
The jockey could not resist the urge to stand high in the irons and flourish his whip at the finish.
"This is just unreal," he said.
The celebratory gesture before the finish line cost him a $500 fine.
Wyndspelle was three-quarters of a length away in second and Helena Baby was a further long neck away in third.
Richards confirmed Melody Belle would return to Hawke's Bay for a shot at the Hastings Triple Crown.
The mare will contest the Windsor Park Plate (1600m) in three weeks then, all going well, the Livamol Classic (2040m) on October 5. Both are group 1 races.
