The Power skipped out to a 35-point lead in the third quarter before the resurgent Hawks slashed the margin to 13 points at three-quarter time.
But then it was Tahau time, with the former defender booting three goals in a row in a stunning burst that set up the upset 15.4 (94) to 8.11 (59) win.
Tahau was goalless in the first half, but burst into action after the break with her five-goal haul taking her to the top of the AFLW goalkickers list.
The Hawks suffered a blow before the game with ruck Lucy Wales ruled out and Scholz took full advantage, with the young star ruck finishing with 21 possessions and 34 hitouts in an outstanding display.
The upset result improved the Power’s win-loss record to 4-6 and snapped a run of four wins for the Hawks, who dropped to 8-2.
It was a mismatch on paper, with the second-placed Hawks against the 13th-ranked Power, but the home side leapt out of the blocks with the first five clearances of the game.
In an opening term of wild momentum swings, Port led early through Houghton, the Irish connection of Aine McDonagh and Aileen Gilroy went back-to-back to put the visitors in front, before Houghton's second restored a four-point lead for the home side at the first break.
The surging Power booted four of five goals to edge further ahead, but Gilroy's second, a long-range special on the run from the 50m, against the run of play kept the Hawks in touch.
Port's forward-half pressure troubled the visitors, with Lauren Arnell's charges leading inside 50s 15-6 in the second quarter, and they pressed home the advantage with the last two goals of the first half, including a brilliant snap in traffic from Ella Boag, to lead by 17 points.
The expected fightback by Hawthorn after the restart didn't immediately materialise.
With the Power playing irresistible footy, Tahau marked strongly twice to boot the opening two goals of the half and Port pushed out to a 35-point lead when skipper Justine Mules-Robinson kicked truly.
But just when the home side looked set to run away with it with five goals in succession, the Hawks dug deep to reel off three goals in a row, with McDonagh adding her second and third to send her side into the last break with the momentum.
It takes two to tango
It was a night of engrossing battles between formidable forward duos, with Indy Tahau and Gemma Houghton at one end and Aine McDonagh and Aileen Gilroy at the other. Houghton set the early pace with two first-quarter goals, and Tahau looked set to break the game open with the first two goals of the second half. McDonagh dragged her side back into it with two late goals in the third quarter, but Tahau gave the Power duo the honours with her superb late blitz in a highly entertaining shootout.
McDonagh makes a move
Hawthorn's first goal of the night from Aine McDonagh was a sight to behold. The Irish star met a bouncing ball on the wing, turned back toward goal and turned on the jets. With two Power defenders in hot pursuit, McDonagh took a bounce, put a brilliant move on an oncoming defender as she crossed 50, and stroked home a stunning goal-of-the-year contender from 45m out.
Up next
The Power will take on cross-town rivals Adelaide at Norwood Oval on Friday night. The Hawks will battle Essendon at Windy Hill on Saturday afternoon.
PORT ADELAIDE 3.1 7.2 10.2 15.4 (94)
HAWTHORN 2.3 4.3 7.7 8.11 (59)
GOALS
Port Adelaide: Tahau 5, Houghton 3, Boag 2, Mules-Robinson 2, Woodland, Pope, Dowrick
Hawthorn: McDonagh 3, Gilroy 2, McLaughlin, Fleming, Bodey
BEST
Port Adelaide: Scholz, Tahau, Woodland, Dowrick, Houghton, Heads
Hawthorn: West, Fleming, Lucas-Rodd, McDonagh, Eardley, Gilroy
INJURIES
Port Adelaide: Nil
Hawthorn: Vukic (concussion)
LATE CHANGE
Hawthorn: Lucy Wales, replaced in the selected side by Elli Symonds
Reports: Nil
Crowd: 3,039 at Alberton Oval
