Niemann cashed in with an eagle at the second extra hole after a trio of big-name local hopes let the famous trophy slip during a wild final round in Sydney.Â
Starting the day four shots behind, Niemann - who plies his trade on the LIV Golf breakaway league after defecting from the PGA Tour - stormed home with a final-round five-under-par 66.
Hoshino closed with a 70 to make the playoff at 14 under but wound up second for the second Sunday running, having last week finished three shots behind emerging Australian superstar Min Woo Loo at the Australian PGA.
Lee will be ruing not saluting again after he entered the final round as co-leader with Hoshino.
And former world No.1 Adam Scott and fellow US PGA Tour star Lucas Herbert also had one hand on the Stonehaven Cup at stages on Sunday.
But all three fan favourites suffered heartbreak, as did Lee's superstar sister Minjee, who had to settle for the runner-up prize in the women's Open after South African Ashleigh Buhai defended her title with a thrilling one-shot win.
While Lee relinquished his lead early, Scott and Herbert had turns at looking likely winners down the stretch, only to falter in incredible fashion.
In the space of seven depressing minutes for Australian golf fans, both suffered triple-bogey sevens to see their hopes vanish.
From 14 under and outright leader with three holes to play, Scott - who started his round on the 10th - drove out of bounds on the par-4 seventh.
After making the long walk back to the tee, he couldn't make par with his second ball and suddenly tumbled to 11 under.
Moments later, Herbert, also at 14 under, found the trees on the ninth hole and recorded his triple-bogey.
He never recovered as Niemann and Hoshino both eventually forced a playoff on the same score the two crestfallen Australians had reached barely two hours earlier.
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