Bronzini was virtual leader of the race mid-way through the stage, courtesy of a solo attack on behalf of teammate and overall hope Linda Villumsen, but still had the power to finish at the front of the sprint when the stage came to the crunch.
Race leader Emma Johansson (Orica-AIS) finished second in her third podium appearance of the race while Pauline Ferrand Prevot (Rabobank-Liv/Giant) was third.
"It's something amazing for me," said Bronzini. "Some people say that I am old now that I am 30, but maybe I'm now good at using my legs with my head. It was a little bit harder than the other days today, because I worked, and I was in the break.
"Today we started with the tactics to help Linda, to try to take the jersey," Bronzini explained, "and in the middle of the race, with about 40km to go, we started to attack. When it was my time to attack they let me go!
"I was alone on the attack for 10 or 15km, and the gap was around a maximum of 50 seconds, but when I was alone I rode in my own rhythm, and not full gas. Alone I could do nothing, but I hoped that the other teams like Orica-AIS would lose power trying to catch me.
"After the first climb of the first lap, I sat up and waited for the bunch, and when they caught me Lauren Kitchen and Mayuko Hagiwara did some attacks to try to make the race harder," Bronzini continued. ". After that Linda did a very, very hard attack in the last 2km, and she had a little gap that Orica-AIS had to close.
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"They caught her with 1km to go, and I was in the wheel of Johansson. Someone from the Australian team started to sprint with 300 metres to go, then I came out from the wheel of Johansson and I won."
Unable to take back that precious second from Johansson, Villumsen remains in second place with two stages to go.
"I'm really proud of the team, because we really tried to do something hard to help Linda, and we were able to do a good job and still win the stage," said Bronzini.
