GREATER Western Sydney's remarkable first season under first-year coach Adam Kingsley has progressed all the way to a preliminary final, defeating a flat Port Adelaide by 23 points.

The 9.16 (70) to 13.15 (93) loss has consigned the Power to a straight-sets exit from finals after finishing third, while GWS will play its second preliminary final against Collingwood in five years.

POWER v GIANTS Full match coverage and stats

Port Adelaide pushed hard in the final term but was its own worst enemy, kicking 1.5 and one out on the full, before Giants skipper Toby Greene pushed the margin out to a safe 27 points with his third goal.

It took until seven minutes into the second quarter for one team to manage successive goals, the Giants jumping out to an eight-point lead after majors to Jesse Hogan and Josh Kelly.

After dominating clearances and uncontested disposals in the first quarter but remaining relatively even on the scoreboard, those two goals opened the floodgates for the orange tsunami.

The Giants were brave and bold, playing with speed and dare through the middle of Adelaide Oval and stunning the parochial home crowd in piling on five straight goals, capped off by a 55m set-shot bomb from Isaac Cumming.

At that point, everything was going so well for the Giants that Sam Taylor managed to deflect a Travis Boak shot with his calf, while facing away from the footy.

GWS left the door open for Port Adelaide, following its five goals with six straight behinds, but the Power could only manage four behinds themselves to trail by 29 points at half-time.

Willie Rioli was comfortably Port Adelaide's most dangerous forward with limited supply, his third goal opening scoring in the second half, while Jason Horne-Francis was creative and Dan Houston steady.

After a quiet first two quarters, Zak Butters burst through to record 11 disposals in the third term, finding some space as the Power began to equalise general play, but they could only trim three points off the margin.

Stephen Coniglio missed last week's elimination final after a poke to the eye at training, but made up for lost time against the Power, recording 22 disposals and a goal in the first half and finishing with 30 and eight clearances.

Callan Ward was crucial in the first half with his disposal inside 50, Lachie Whitfield's pace off half-back kickstarted the Giants' run, while Toby Bedford found space on the wing and across half-forward time and time again.

A first-half spanking
While the scoreboard was relatively even in the first quarter, there were warning signs for Port Adelaide in clearances and uncontested footy. Those numbers exploded in the second quarter as the Giants took control, the Power going into the main break down 128-66 in uncontested possessions, 214-136 in overall disposals and 29-12 in clearances.

The rollercoaster match of Kieren Briggs
The newly re-signed Briggs was outstanding in the first half, giving his midfielders first use of the ball, winning the aerial battle and competing at ground level. The Power actually chose to sub their ruck Scott Lycett, who had spent some time getting treatment on an ankle injury, only to see Briggs suffer a shoulder injury himself just minutes later. The Giant returned for the last quarter and played well (32 hitouts and eight clearances), but will have all eyes watching at training this week.

Underdone Port players backfire
Trent McKenzie was a test coming into the game with an ankle complaint and looked a step off the pace on Saturday night, struggling to keep up with Jesse Hogan at times. Key forward Charlie Dixon was playing his first match since a round 20 foot injury and struggled to get near the footy for the first three quarters.

PORT ADELAIDE                          4.1     5.6         8.7        9.16     (70)
GREATER WESTERN SYDNEY     4.4     9.11     11.15     13.15     (93) 

GOALS
Port Adelaide: Rioli 3, Marshall 2, Horne-Francis, Drew, Lord, Dixon
Greater Western Sydney: Hogan 4, Greene 3, Coniglio 2, Daniels, Kelly, Cumming, Riccardi 

BEST
Port Adelaide: Horne-Francis, Houston, Rioli, Butters, Boak
Greater Western Sydney: Coniglio, Ward, Briggs, Hogan, Bedford, Whitfield 

INJURIES
Port Adelaide: Nil
Greater Western Sydney: Briggs (shoulder) 

SUBSTITUTES
Port Adelaide: Jeremy Finlayson (replaced Scott Lycett in the third quarter)
Greater Western Sydney: Xavier O'Halloran (replaced Callum Brown in the fourth quarter) 

Crowd: 45,520 at Adelaide Oval