Leading the PS5.4 million (AU$9.7 million) tournament by one shot at the halfway stage, Herbert unravelled in terrible conditions on day three with an eight-over-par 79.

However, the 24-year-old surged into the lead with six birdies in the first 10 holes on Sunday, and recovered from a bogey on the 12th with further gains on the 15th and 16th, only to crucially drop a shot on the 17th.

The 24-year-old from Victoria finished level with Scotland's Marc Warren on nine-under.

At the top of the leaderboard, Fleetwood birdied the last hole of regulation play to match Rai's total of 11-under but then missed from a metre for par on the first play-off hole.

“It's hard to sum up. It wasn't nice in that fashion, Tommy had finished off incredibly and it's not nice to see him miss that but it feels incredible.” – Aaron Rai

Rai, who finished second in the Irish Open seven days ago, said: "It's hard to sum up. It wasn't nice in that fashion, Tommy had finished off incredibly and it's not nice to see him miss that but it feels incredible."

Overnight leader Robert Rock looked set to match Rai's total of 64 after he birdied the 10th, 13th, 15th and 16th, only to bogey the last after a clumsy chip from just short of the green.

Playing partner Fleetwood had missed from three feet for birdie on the 16th but bounced back to hole from 15 feet on the last to take the event into extra holes for the third time in four years.

Rock, who began the day with a two-shot lead, finished alone in third on 10 under.

Adelaide's Wade Ormsby carded a final-day 73 to finish on five-under, while fellow Australians Min Woo Lee (-3), Maverick Antcliff (-2) and Scott Hend (+3) were also in action.