A CAREER-BEST showing from former No.1 pick Jason Horne-Francis has led Port Adelaide to a seven-point win on the road over the ladder-leading St Kilda.

Jeremy Finlayson was also instrumental in the win, taking two crucial marks in the dying minutes as the spare in defence to seal the 12.11 (83) to 11.10 (76) victory at Marvel Stadium.

SAINTS v POWER Full match coverage and stats

The lead changed hands four times in the second half as neither side could shake off the other, with fierce tackling (and a subsequent lack of composure) a feature.

Josh Battle had a moment he'd like to forget midway through the last term, called to play on after a half-step on the last line of defence. 

His kick was brilliantly smothered by Charlie Dixon, with Sam Powell-Pepper kicking the resultant goal and the margin was out to eight. The Power weren't headed from there.

Horne-Francis was Port Adelaide's most dynamic midfielder even when the team was struggling in the first quarter, the second-year bull providing some much-needed speed around the stoppages.

He faded somewhat in the second half, but recorded a career-high 10 clearances to half-time (11 for the game) and finished with 25 disposals and seven tackles.

Port Adelaide struggled to make a meaningful impact in attack in the first quarter, almost sleepy in setting up its forward structure, but it worked its way back into the game beautifully. 

St Kilda had shown just why it was sitting pretty in top spot in the first quarter, playing with positivity and finding a variety of paths to goal, with its defence standing firm and Rowan Marshall directing play around the ground.

The Power didn't drop their heads despite an 18-point deficit at quarter-time, improving in their contested-ball wins and increasing their tackle pressure to kick four straight goals, taking the lead for the first time at the 17-minute mark of the second quarter.

The second-term woes of the Saints were starkly demonstrated in the stats, recording just four behinds from 16 inside-50s, while the visitors were impressively efficient with 4.5 from 10 entries.

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Jack Sinclair (33) worked hard off the half-back flank all match, Jack Steele (28 and nine tackles) tried desperately to drag the Saints over the line and Marshall (28 hitouts, 26 disposals) was imperious in the ruck against the young Brynn Teakle. 

Xavier Duursma clashed knees with Marshall halfway through the first term, and struggled to get any speed up when he returned to the field following treatment. He was subbed at the first break.

Nasiah Wanganeen-Milera was crunched in a teal sandwich late in the second and the in-form Cal Wilkie needed his right ankle re-strapped in the third, but both played out the game.

Never take your eye off a Rioli
In a pulsating third term, it was Junior Rioli who gave Port Adelaide some much-needed breathing space, kicking the last two goals of the quarter. His second was simply sublime, spinning one way before baulking around a desperately lunging Dougal Howard to snap truly. It meant the Power carried an eight-point lead into the last quarter.

Efficiency is key
St Kilda had no trouble getting its hands on the footy, but over-possessed it compared to Port Adelaide. The Power went direct, moving the ball faster than the Saints could set up in defence. They had 36 fewer touches by three-quarter time, but were up by eight points. The last term was much of the same, 38 disposals down but seven points up on the siren. Port Adelaide also had five fewer inside 50s.

An important win on the road
This game was seen as a litmus test for Port Adelaide, up against the first-placed Saints on their home deck. But the Power strangled the Saints at their own game, stifling their movement down the ground and perhaps providing a teal-print on how to handle the new-look St Kilda. It takes Port Adelaide to a 5-2 record, and a chance to finish the round in the top four.

ST KILDA                 5.2     5.6     8.8     11.10      (76)
PORT ADELAIDE     2.2     6.7     9.10     12.11     (83)

GOALS
St Kilda: Owens 2, Gresham 2, Higgins, Cordy, Membrey, Wood, Butler, Steele, Clark
Port Adelaide: Rioli 2, Powell-Pepper 2, Dixon 2, Finlayson 2, Duursma, Boak, Houston, McEntee

BEST
St Kilda: Steele, Sinclair, Marshall, Wanganeen-Milera, Wilkie
Port Adelaide: Horne-Francis, Boak, Butters, Houston, Powell-Pepper

INJURIES
St Kilda: Nil
Port Adelaide: Duursma (left knee)

SUBSTITUTES
St Kilda: Marcus Windhager (replaced Cordy in the third quarter)
Port Adelaide: Riley Bonner (replaced Duursma at quarter-time)

Crowd: 25,845 at Marvel Stadium