MORE than four decades have passed since Australian Football Hall of Fame coach David Parkin came to define the third term as the "premiership quarter". And for all that has changed in the game since Parkin coined the phrase in 1982, the concept that dominance in one 20-minute period marks a flag winner highlights a trend in Port Adelaide's results.

Port Adelaide this season has:

FALLEN 15 points behind Brisbane at half-time of the season-opener at Adelaide Oval ... and blitzed with 8.4 during the third term to break a five-game losing streak to the Queensland club by 54 points.

TRAILED Essendon by 14 points at half-time of the round eight clash at Adelaide Oval ... to respond with 4.5 during the third term (to have 9.16 on the scoreboard). The five-point win (with 12.20 at full-time) put Port Adelaide at 6-2 on the ladder and consolidating a top-four campaign.

FACED a seven-point deficit to a refreshed Geelong at half-time of the Thursday night classic with the AFL premier at Adelaide Oval in round 14 while having to work to against the physical demands of three games on consecutive six-day breaks ... to respond with 7.1 during the third term to set up a 38-point win

CHASED Gold Coast's assertive start at Adelaide Oval on Saturday night to have a six-point deficit at half-time vanish with a game-changing nine-goal burst (9.2 to be precise) for a 33-point win. The record-setting streak is now 13 ... and a trend has emerged.

Port Adelaide - the team defined by contested football in recent years - is, as Sydney coach John Longmire noted last season, at its best when it plays "pressure football". The intercepts created by pressure plays become goals. The opposition turnovers - under that manic pressure - become the method to locking the ball inside Port Adelaide's forward half. Momentum shifts dramatically in Port Adelaide's favour.

Port Adelaide is the AFL's top-ranked team this season for punishing teams on intercepts. This amounts to two goals on the scoreboard. Six of Port Adelaide's nine goals on Saturday night were from intercepts of Gold Coast plays.

RICHMOND should have felt the third-quarter scorch in round 11 at the MCG ... but Port Adelaide put 2.5 on the scoreboard before winning by 10 points with a final score of 10.17. Goalkicking accuracy remains a curse in this sport.

Port Adelaide's match-changing, momentum-swinging blitzes are not just a third-quarter phenomenon that invokes Parkin's premiership pointer.

IN rain and under intense pressure, Port Adelaide charged to a four-point win against Essendon at the MCG in round 16 with 5.3 - and Dan Houston's 55-metre goal after the siren - during the last term.

AFTER leading North Melbourne by just one point at quarter-time in Hobart, Port Adelaide delivered an eight-goal second term that infuriated opposition coach Alastair Clarkson.

EXPOSED Hawthorn to the super-octane scoring from the start at Adelaide Oval in round 12 - 9.3 in the first term followed by 7.6 in the second.

Be it any quarter - and generally when Port Adelaide needs to dig itself out of a hole - Hinkley's crew can put together a significant goal rush.

There is a "Port Adelaide way" - as well noted by Longmire - with high-pressure football continually stripping the opposition of the Sherrin to underpin these blitzes.

There is a belief and confidence in this method that has grown with each win during the streak that began with intense football at the SCG against Sydney in round four, after all had been cast as untenable at 1-2.

And there is the need for the occasional reminder of all that propels the Port Adelaide blitzes, as senior coach Ken Hinkley did with a stern voice at half-time on Saturday night.

His players were "millionaires using a credit card" - with more show tricks than show - for the first hour against Gold Coast. Hinkley dubbed the ball use by his players as poor execution.

"I said I was not super pleased with the consistency of our performance ...," Hinkley says with a diplomatic reflection of his half-time message to his players who were needing to recalibrate their focus.

"If you do that (stern rev up) every week, it will get you nowhere. The art of coaching is to know when (to speak that way). And the players know when you have that conversation that they have some responsibility (to change their behaviour).

"They proved during the third quarter that they knew what their responsibility was."

Port Adelaide's record in third terms during the 13-game winning streak is - WON 7; lost 5 and drawn one SCORED 48.36; conceded 43.26

SYDNEY: Lost, 1.2 to 3.4
WESTERN BULLDOGS: Lost, 1.2 to 3.1
WEST COAST: Won, 4.3 to 4.2
ST KILDA: Won, 3.3 to 3.2
ESSENDON: Won, 4.5 to 2.2
NORTH MELBOURNE: Won, 4.4 to 4.1
MELBOURNE: Lost, 3.1 to 7.2
RICHMOND: Lost, 2.5 to 3.2
HAWTHORN: Drawn, 5.3 to 5.3
WESTERN BULLDOGS: Won, 4.4 to 2.1
GEELONG: Won, 7.1 to 3.1
ESSENDON: Lost, 1.1 to 3.4
GOLD COAST: Won, 9.2 to 1.1

Parkin's third-quarter theme has stood the test of time. Port Adelaide will have to do the same while the longest home-and-away series in the league's history has still six rounds to play before the top-eight finals.

ON REVIEW: HE did it again. Dan Houston did it again.

Second time it had to be easier, right? Third quarter, 10 minutes in ... Port Adelaide on a mometum-charged nine-goal blitz to the Riverbank end of Adelaide Oval ... compared with 18 seconds remaining on the clock and the scoreboard at the MCG saying a goal was needed if Port Adelaide was to beat Essendon.

Both kicks, from outside 50, were perfect.

Neither was the same for the backdrop of pressure, condition or consequences.

So in a season in which goalkicking accuracy has fallen to a record low how does an AFL senior coach prepare his players for moments that can decide a match, as noted with Houston's classic at the MCG?

"Not just this year," says Port Adelaide senior coach Ken Hinkley of the troubled goalkicking conversion across the league. "It is a challenging part of the game and has been for 100 years. Everyone will ask, 'What are you doing about it?' Or, 'How are you working on it?

"We spend and invest a lot of time on goalkicking. But we just can't replicate the pressure of game day (at practice). And that pressure affects people in different ways. They work on it mentally, they work on it physically. They do all the things they need to.

"But accuracy remains a challenge.

"We have seen players taken up different shots at goal. We have seen different techniques emerge during the past 10-15 years. The game will probably always throw up that inaccuracy at goal ..."

Port Adelaide on Saturday night against Gold Coast scored 16.10, with five kicks hitting the post - twice by Jeremy Finlayson, the first time from a basic, routine set shot directly in front of goal - after he had accurately snapped at the Riverbank end from a situation that would be impossible to replicate at training at Alberton Oval.

In 16 games this season, Port Adelaide has scored 222.208 (51 per cent conversion without counting shots that completely missed). In eight of the 16 matches, Port Adelaide has scored more goals than behinds - the best conversion at 64 per cent with 23.13 against Hawthorn at Adelaide Oval in round 13 and the worst at 37 per cent with the 12.20 scored against Essendon at Adelaide Oval in round eight and 10.17 against Richmond at the MCG in round 11.