With centre Matt Hodgson in foul trouble and match-winner Lamar Patterson contained after quarter-time, Magnay stood up to the Kings’ might with a sparkling 23 points, 14 rebounds and two blocks.
He was the dominant big man, easily overshadowing Bogut and Jae’Sean Tate, the Kings star who promised much early before going quiet.
Sydney’s Casper Ware was a huge threat and finished with a game-high 26 points but lacked the helpers to haul the NBL leaders across the line.
Bullets forward Magnay could not have picked a harder assignment for his first NBL career start. The 21-year-old took on former NBA star Bogut and gun import Tate and held his own in the first quarter.
It was impossible to match the highlight-reel dunk Tate launched to help the Kings to an eight-point lead at the end of a lively first quarter.
Sydney looked in control when they led by 12 points early in the second quarter. That was before Magnay and Taylor Braun injected some crackle back into the Bullets defence.
Taylor dragged the Bullets back into the contest, frequently switching between difficult guarding assignments on Tate and Ware.
Magnay landed 13 points for the quarter but more importantly emerged as the menacing figure to make the Kings re-think their post strategy.
A boilover beckoned when the efforts of Magnay and Cam Gliddon powered the home side out to a 14-point lead early in the third quarter.
Brisbane could have cracked when Patterson fouled out towards the end of the final term but they remained steady in the face of the Ware-led Kings.