Watch a full replay of Sunday's feature plus Alex Steedman's interview with an exultant Richard Hannon.
Building on her solid fifth in the Queen Mary at Royal Ascot, the daughter of Dandy Man continued the Hannon family's dominance of the five-furlong dash, which the Marlborough handler's father Richard senior claimed seven times ahead of his retirement.
Travelling into the race powerfully for Sean Levey, the well-supported 100-30 favourite quickly pulled clear once putting the afterburners on and crossed the line two and three-quarter lengths clear of Jojo Rabbit.
Hannon said: "She has improved all year and won that very well. If you have a look at her coming out of the gates she got knocked around a fair bit. She is a tough thing. Sean is adamant she wants seven furlongs. It is the owners' first horse. I met them at Newbury for the first time just standing around.
"We need to keep new people coming into this sport and this is what this race is about. For them it is a lot of prize-money, it's a big day and it's on television."
He added: "She ran very well at Royal Ascot and I thought it was a good Queen Mary. We might go to the Lowther (at York), but she is in a sales race in Ireland. She is definitely Group class."
It was a day to remember for first-time owners Ray and Claire McMurray and their son Oliver, who were on hand to see Happy Romance on the track for the first time.
The former said: "I can't believe it. Richard Hannon has done a fantastic job and we are living the dream. My son dragged me into this as he phoned me last year saying he had seen a nice yearling through Richard Hannon and I said 'let's go for it'.
"It is our first time as owners and it is the first time we have seen the horse on a racecourse as an owner and it has been a great experience so far, even though it is behind closed doors.
"We were very nervous going into the Queen Mary, but she pushed as hard as she could and did well. We had great expectations coming here today."Get your free Racing TV fleece - the latest in our range of high-class Racing TV merchandise! Click here for more details.
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