Alexander Volkanovski has fallen short in his bid to become the first Australian to simultaneously hold two UFC titles, losing to lightweight champion Islam Makhachev in Perth.
In front of a raucous sold-out crowd at RAC Arena on Sunday, Volkanovski could not overcome Russian grappler Makhachev in a headline fight which went the distance across five rounds.
Makhachev achieved multiple takedowns and withstood a final-round barrage to claim a unanimous points victory and seize the UFC's No.1 pound-for-pound ranking.
Wollongong-based featherweight champion Volkanovski had been vying to become just the fifth UFC fighter to hold two titles at once.
It is his first defeat in the Octagon and just the second in a professional career in which he has notched 25 wins.
Hometown welterweight Jack Della Maddalena earlier brought the house down with a first-round submission victory over American Randy Brown.
Rising star Della Maddalena needed just two minutes 13 seconds to claim victory, knocking Brown to the ground with a fierce blow before applying a rear-naked chokehold which forced his opponent to tap.
The 26-year-old has scored first-round victories in each of his first four UFC bouts.
Yair Rodriguez dominated Josh Emmett in an interim featherweight title bout which establishes the Mexican as the No.1 contender to challenge Volkanovski once he drops back down in weight to defend his belt.
Brisbane heavyweight Justin Tafa needed just over a minute to knock out Parker Porter, while light heavyweight compatriot Jimmy Crute fought out an entertaining majority draw with America's Alonzo Menifield.