Browne took Boomsara ($6) to lead Saturday's 1350m-race from a wide barrier and kept up the momentum to beat Pennino ($31) by 4-1/2 lengths with a short half head to Light Up the Room ($10).
Favourite Outback Barbie ($2.15) effectively lost her chance in the backwash when Jackson Murphy came off Granny Red Shoes near the 650m.
Murphy was conscious and taken to hospital for precautionary X-rays after complaining of pain in his right hand and leg.
Boomsara won the $150,000 Aquis Jewel and was placed in the Group Two BRC Sires' Produce Stakes and the Group Three Ken Russell Memorial as two-year-old.
He showed how well he had come back when second to star three-year-old Zoustyle at his previous start.
“I have been saying all along that we won't see the best of him until he got out to 1350 and 1400 metres,” Munce said.
“It was a month between runs today and he will be improved for the Guineas. I give him a real chance of winning the race.”
Munce won the Magic Millions 2YO Classic three times as a jockey but never won the Guineas.
Boomsara cost $45,000 at the Magic Millions March sale and lifted his prize money to $360,000.
“He has been terrific for us and his owners who include the McAlpines of Eureka Stud who stand his sire Spirit of Boom,” Munce said.